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Saturday, July 11, 2020

History of artificial life

From Wikipedia, the free encyclopedia
 
The idea of human artifacts being given life has fascinated humankind for as long as people have been recording their myths and stories. Whether Pygmalion or Frankenstein, humanity has been fascinated with the idea of artificial life.

Pre-computer

Automatons were quite a novelty. In the days before computers and electronics, some were very sophisticated, using pneumatics, mechanics, and hydraulics. The first automata were conceived during the third and second centuries BC and these were demonstrated by the theorems of Hero of Alexandria, which included sophisticated mechanical and hydraulic solutions. Many of his notable works were included in the book Pneumatics, which was also used for constructing machines until early modern times. In 1490, Leonardo da Vinci also constructed an armored knight, which is considered the first humanoid robot in Western civilization.

Other early famous examples include al-Jazari's humanoid robots. This Arabic inventor once constructed a band of automata, which can be commanded to play different pieces of music. There is also the case of Jacques de Vaucanson's artificial duck exhibited in 1735, which had thousands of moving parts and one of the first to mimic a biological system. The duck could reportedly eat and digest, drink, quack, and splash in a pool. It was exhibited all over Europe until it fell into disrepair.

However, it wasn't until the invention of cheap computing power that artificial life as a legitimate science began in earnest, steeped more in the theoretical and computational than the mechanical and mythological.

1950s–1970s

One of the earliest thinkers of the modern age to postulate the potentials of artificial life, separate from artificial intelligence, was math and computer prodigy John von Neumann. At the Hixon Symposium, hosted by Linus Pauling in Pasadena, California in the late 1940s, von Neumann delivered a lecture titled "The General and Logical Theory of Automata." He defined an "automaton" as any machine whose behavior proceeded logically from step to step by combining information from the environment and its own programming, and said that natural organisms would in the end be found to follow similar simple rules. He also spoke about the idea of self-replicating machines. He postulated a machine – a kinematic automaton – made up of a control computer, a construction arm, and a long series of instructions, floating in a lake of parts. By following the instructions that were part of its own body, it could create an identical machine. He followed this idea by creating (with Stanislaw Ulam) a purely logic-based automaton, not requiring a physical body but based on the changing states of the cells in an infinite grid – the first cellular automaton. It was extraordinarily complicated compared to later CAs, having hundreds of thousands of cells which could each exist in one of twenty-nine states, but von Neumann felt he needed the complexity in order for it to function not just as a self-replicating "machine", but also as a universal computer as defined by Alan Turing. This "universal constructor" read from a tape of instructions and wrote out a series of cells that could then be made active to leave a fully functional copy of the original machine and its tape. Von Neumann worked on his automata theory intensively right up to his death, and considered it his most important work.

Homer Jacobson illustrated basic self-replication in the 1950s with a model train set – a seed "organism" consisting of a "head" and "tail" boxcar could use the simple rules of the system to consistently create new "organisms" identical to itself, so long as there was a random pool of new boxcars to draw from. Edward F. Moore proposed "Artificial Living Plants", which would be floating factories which could create copies of themselves. They could be programmed to perform some function (extracting fresh water, harvesting minerals from seawater) for an investment that would be relatively small compared to the huge returns from the exponentially growing numbers of factories. Freeman Dyson also studied the idea, envisioning self-replicating machines sent to explore and exploit other planets and moons, and a NASA group called the Self-Replicating Systems Concept Team performed a 1980 study on the feasibility of a self-building lunar factory.

University of Cambridge professor John Horton Conway invented the most famous cellular automaton in the 1960s. He called it the Game of Life, and publicized it through Martin Gardner's column in Scientific American magazine.

1970s–1980s

Philosophy scholar Arthur Burks, who had worked with von Neumann (and indeed, organized his papers after Neumann's death), headed the Logic of Computers Group at the University of Michigan. He brought the overlooked views of 19th century American thinker Charles Sanders Peirce into the modern age. Peirce was a strong believer that all of nature's workings were based on logic (though not always deductive logic). The Michigan group was one of the few groups still interested in alife and CAs in the early 1970s; one of its students, Tommaso Toffoli argued in his PhD thesis that the field was important because its results explain the simple rules that underlay complex effects in nature. Toffoli later provided a key proof that CAs were reversible, just as the true universe is considered to be.




Christopher Langton was an unconventional researcher, with an undistinguished academic career that led him to a job programming DEC mainframes for a hospital. He became enthralled by Conway's Game of Life, and began pursuing the idea that the computer could emulate living creatures. After years of study (and a near-fatal hang-gliding accident), he began attempting to actualize Von Neumann's CA and the work of Edgar F. Codd, who had simplified Von Neumann's original twenty-nine state monster to one with only eight states. He succeeded in creating the first self-replicating computer organism in October 1979, using only an Apple II desktop computer. He entered Burks' graduate program at the Logic of Computers Group in 1982, at the age of 33, and helped to found a new discipline.


Langton's official conference announcement of Artificial Life I was the earliest description of a field which had previously barely existed:
Artificial life is the study of artificial systems that exhibit behavior characteristic of natural living systems. It is the quest to explain life in any of its possible manifestations, without restriction to the particular examples that have evolved on earth. This includes biological and chemical experiments, computer simulations, and purely theoretical endeavors. Processes occurring on molecular, social, and evolutionary scales are subject to investigation. The ultimate goal is to extract the logical form of living systems.
Microelectronic technology and genetic engineering will soon give us the capability to create new life forms in silico as well as in vitro. This capacity will present humanity with the most far-reaching technical, theoretical and ethical challenges it has ever confronted. The time seems appropriate for a gathering of those involved in attempts to simulate or synthesize aspects of living systems.
Ed Fredkin founded the Information Mechanics Group at MIT, which united Toffoli, Norman Margolus, Gerard Vichniac, and Charles Bennett. This group created a computer especially designed to execute cellular automata, eventually reducing it to the size of a single circuit board. This "cellular automata machine" allowed an explosion of alife research among scientists who could not otherwise afford sophisticated computers. 

In 1982, computer scientist named Stephen Wolfram turned his attention to cellular automata. He explored and categorized the types of complexity displayed by one-dimensional CAs, and showed how they applied to natural phenomena such as the patterns of seashells and the nature of plant growth. Norman Packard, who worked with Wolfram at the Institute for Advanced Study, used CAs to simulate the growth of snowflakes, following very basic rules.

Computer animator Craig Reynolds similarly used three simple rules to create recognizable flocking behaviour in a computer program in 1987 to animate groups of boids. With no top-down programming at all, the boids produced lifelike solutions to evading obstacles placed in their path. Computer animation has continued to be a key commercial driver of alife research as the creators of movies attempt to find more realistic and inexpensive ways to animate natural forms such as plant life, animal movement, hair growth, and complicated organic textures.

J. Doyne Farmer was a key figure in tying artificial life research to the emerging field of complex adaptive systems, working at the Center for Nonlinear Studies (a basic research section of Los Alamos National Laboratory), just as its star chaos theorist Mitchell Feigenbaum was leaving. Farmer and Norman Packard chaired a conference in May 1985 called "Evolution, Games, and Learning", which was to presage many of the topics of later alife conferences.

2000s

On the ecological front, research regarding the evolution of animal cooperative behavior (started by W. D. Hamilton in the 1960s resulting in theories of kin selection, reciprocity, multilevel selection and cultural group selection) was re-introduced via artificial life by Peter Turchin and Mikhail Burtsev in 2006. Previously, game theory has been utilized in similar investigation, however, that approach was deemed to be rather limiting in its amount of possible strategies and debatable set of payoff rules. The alife model designed here, instead, is based upon Conway's Game of Life but with much added complexity (there are over 101000 strategies that can potentially emerge). Most significantly, the interacting agents are characterized by external phenotype markers which allows for recognition amongst in-group members. In effect, it is shown that given the capacity to perceive these markers, agents within the system are then able to evolve new group behaviors under minimalistic assumptions. On top of the already known strategies of the bourgeois-hawk-dove game, here two novel modes of cooperative attack and defense arise from the simulation.

For the setup, this two-dimensional artificial world is divided into cells, each empty or containing a resource bundle. An empty cell can acquire a resource bundle with a certain probability per unit of time and lose it when an agent consumes the resource. Each agent is plainly constructed with a set of receptors, effectors (the components that govern the agents' behavior), and neural net which connect the two. In response to the environment, an agent may rest, eat, reproduce by division, move, turn and attack. All actions expend energy taken from its internal energy storage; once that is depleted, the agent dies. Consumption of resource, as well as other agents after defeating them, yields an increase in the energy storage. Reproduction is modeled as being asexual while the offspring receive half the parental energy. Agents are also equipped with sensory inputs that allow them to detect resources or other members within a parameter in addition to its own level of vitality. As for the phenotype markers, they do not influence behavior but solely function as indicator of 'genetic' similarity. Heredity is achieved by having the relevant information be inherited by the offspring and subjected to a set rate of mutation.

The objective of the investigation is to study how the presence of phenotype markers affects the model's range of evolving cooperative strategies. In addition, as the resource available in this 2D environment is capped, the simulation also serves to determine the effect of environmental carrying capacity on their emergence.




One previously unseen strategy is termed the "raven". These agents leave cells with in-group members, thus avoiding intra-specific competition, and attack out-group members voluntarily. Another strategy, named the 'starling', involves the agent sharing cells with in-group members. Despite individuals having smaller energy storage due to resource partitioning, this strategy permits highly effective defense against large invaders via the advantage in numbers. Ecologically speaking, this resembles the mobbing behavior that characterizes many species of small birds when they collectively defend against the predator.


In conclusion, the research claims that the simulated results have important implications for the evolution of territoriality by showing that within the alife framework it is possible to "model not only how one strategy displaces another, but also the very process by which new strategies emerge from a large quantity of possibilities".

Work is also underway to create cellular models of artificial life. Initial work on building a complete biochemical model of cellular behavior is underway as part of a number of different research projects, namely Blue Gene which seeks to understand the mechanisms behind protein folding.

Artificial life

From Wikipedia, the free encyclopedia

Artificial life (often abbreviated ALife or A-Life) is a field of study wherein researchers examine systems related to natural life, its processes, and its evolution, through the use of simulations with computer models, robotics, and biochemistry. The discipline was named by Christopher Langton, an American theoretical biologist, in 1986. In 1987 Langton organized the first conference on the field, in Los Alamos, New Mexico. There are three main kinds of alife, named for their approaches: soft, from software; hard, from hardware; and wet, from biochemistry. Artificial life researchers study traditional biology by trying to recreate aspects of biological phenomena.

A Braitenberg vehicle simulation, programmed in breve, an artificial life simulator

Overview

Artificial life studies the fundamental processes of living systems in artificial environments in order to gain a deeper understanding of the complex information processing that define such systems. These topics are broad, but often include evolutionary dynamics, emergent properties of collective systems, biomimicry, as well as related issues about the philosophy of the nature of life and the use of lifelike properties in artistic works.

Philosophy

The modeling philosophy of artificial life strongly differs from traditional modeling by studying not only "life-as-we-know-it" but also "life-as-it-might-be".

A traditional model of a biological system will focus on capturing its most important parameters. In contrast, an alife modeling approach will generally seek to decipher the most simple and general principles underlying life and implement them in a simulation. The simulation then offers the possibility to analyse new and different lifelike systems.

Vladimir Georgievich Red'ko proposed to generalize this distinction to the modeling of any process, leading to the more general distinction of "processes-as-we-know-them" and "processes-as-they-could-be".

At present, the commonly accepted definition of life does not consider any current alife simulations or software to be alive, and they do not constitute part of the evolutionary process of any ecosystem. However, different opinions about artificial life's potential have arisen:
  • The strong alife (cf. Strong AI) position states that "life is a process which can be abstracted away from any particular medium" (John von Neumann). Notably, Tom Ray declared that his program Tierra is not simulating life in a computer but synthesizing it.
  • The weak alife position denies the possibility of generating a "living process" outside of a chemical solution. Its researchers try instead to simulate life processes to understand the underlying mechanics of biological phenomena.

Software-based ("soft")

Techniques

  • Cellular automata were used in the early days of artificial life, and are still often used for ease of scalability and parallelization. Alife and cellular automata share a closely tied history.
  • Artificial neural networks are sometimes used to model the brain of an agent. Although traditionally more of an artificial intelligence technique, neural nets can be important for simulating population dynamics of organisms that can learn. The symbiosis between learning and evolution is central to theories about the development of instincts in organisms with higher neurological complexity, as in, for instance, the Baldwin effect.

Notable simulators

This is a list of artificial life/digital organism simulators, organized by the method of creature definition.

Name Driven By Started Ended
ApeSDK (formerly Noble Ape) language/social simulation 1996 ongoing
Avida executable DNA 1993 ongoing
Biogenesis executable DNA 2006 ongoing
Neurokernel Geppetto 2014 ongoing
Creatures neural net/simulated biochemistry 1996-2001 Fandom still active to this day, some abortive attempts at new products
Critterding neural net 2005 ongoing
Darwinbots executable DNA 2003 ongoing
DigiHive executable DNA 2006 ongoing
DOSE executable DNA 2012 ongoing
EcoSim Fuzzy Cognitive Map 2009 ongoing
Framsticks executable DNA 1996 ongoing
Geb neural net 1997 ongoing
OpenWorm Geppetto 2011 ongoing
Polyworld neural net 1990 ongoing
Primordial Life executable DNA 1994 2003
ScriptBots executable DNA 2010 ongoing
TechnoSphere modules 1995
Tierra executable DNA 1991 2004
3D Virtual Creature Evolution neural net 2008 NA

Program-based

Program-based simulations contain organisms with a complex DNA language, usually Turing complete. This language is more often in the form of a computer program than actual biological DNA. Assembly derivatives are the most common languages used. An organism "lives" when its code is executed, and there are usually various methods allowing self-replication. Mutations are generally implemented as random changes to the code. Use of cellular automata is common but not required. Another example could be an artificial intelligence and multi-agent system/program.

Module-based

Individual modules are added to a creature. These modules modify the creature's behaviors and characteristics either directly, by hard coding into the simulation (leg type A increases speed and metabolism), or indirectly, through the emergent interactions between a creature's modules (leg type A moves up and down with a frequency of X, which interacts with other legs to create motion). Generally these are simulators which emphasize user creation and accessibility over mutation and evolution.

Parameter-based

Organisms are generally constructed with pre-defined and fixed behaviors that are controlled by various parameters that mutate. That is, each organism contains a collection of numbers or other finite parameters. Each parameter controls one or several aspects of an organism in a well-defined way.

Neural net–based

These simulations have creatures that learn and grow using neural nets or a close derivative. Emphasis is often, although not always, more on learning than on natural selection.

Complex systems modeling

Mathematical models of complex systems are of three types: black-box (phenomenological), white-box (mechanistic, based on the first principles) and grey-box (mixtures of phenomenological and mechanistic models). In black-box models, the individual-based (mechanistic) mechanisms of a complex dynamic system remain hidden.

Mathematical models for complex systems
 
Black-box models are completely nonmechanistic. They are phenomenological and ignore a composition and internal structure of a complex system. We cannot investigate interactions of subsystems of such a non-transparent model. A white-box model of complex dynamic system has ‘transparent walls’ and directly shows underlying mechanisms. All events at micro-, meso- and macro-levels of a dynamic system are directly visible at all stages of its white-box model evolution. In most cases mathematical modelers use the heavy black-box mathematical methods, which cannot produce mechanistic models of complex dynamic systems. Grey-box models are intermediate and combine black-box and white-box approaches.

Logical deterministic individual-based cellular automata model of single species population growth
 
Creation of a white-box model of complex system is associated with the problem of the necessity of an a priori basic knowledge of the modeling subject. The deterministic logical cellular automata are necessary but not sufficient condition of a white-box model. The second necessary prerequisite of a white-box model is the presence of the physical ontology of the object under study. The white-box modeling represents an automatic hyper-logical inference from the first principles because it is completely based on the deterministic logic and axiomatic theory of the subject. The purpose of the white-box modeling is to derive from the basic axioms a more detailed, more concrete mechanistic knowledge about the dynamics of the object under study. The necessity to formulate an intrinsic axiomatic system of the subject before creating its white-box model distinguishes the cellular automata models of white-box type from cellular automata models based on arbitrary logical rules. If cellular automata rules have not been formulated from the first principles of the subject, then such a model may have a weak relevance to the real problem.

Logical deterministic individual-based cellular automata model of interspecific competition for a single limited resource

Hardware-based ("hard")

Hardware-based artificial life mainly consist of robots, that is, automatically guided machines able to do tasks on their own.

Biochemical-based ("wet")

Biochemical-based life is studied in the field of synthetic biology. It involves e.g. the creation of synthetic DNA. The term "wet" is an extension of the term "wetware". Efforts toward "wet" artificial life focus on engineering live minimal cells from living bacteria Mycoplasma laboratorium and in building non-living biochemical cell-like systems from scratch.

In May 2019, researchers, in a milestone effort, reported the creation of a new synthetic (possibly artificial) form of viable life, a variant of the bacteria Escherichia coli, by reducing the natural number of 64 codons in the bacterial genome to 59 codons instead, in order to encode 20 amino acids.

Open problems

How does life arise from the nonliving?
  • Generate a molecular proto-organism in vitro.
  • Achieve the transition to life in an artificial chemistry in silico.
  • Determine whether fundamentally novel living organizations can exist.
  • Simulate a unicellular organism over its entire life cycle.
  • Explain how rules and symbols are generated from physical dynamics in living systems.
What are the potentials and limits of living systems?
  • Determine what is inevitable in the open-ended evolution of life.
  • Determine minimal conditions for evolutionary transitions from specific to generic response systems.
  • Create a formal framework for synthesizing dynamical hierarchies at all scales.
  • Determine the predictability of evolutionary consequences of manipulating organisms and ecosystems.
  • Develop a theory of information processing, information flow, and information generation for evolving systems.
How is life related to mind, machines, and culture?
  • Demonstrate the emergence of intelligence and mind in an artificial living system.
  • Evaluate the influence of machines on the next major evolutionary transition of life.
  • Provide a quantitative model of the interplay between cultural and biological evolution.
  • Establish ethical principles for artificial life.

Related subjects

  1. Artificial intelligence has traditionally used a top down approach, while alife generally works from the bottom up.
  2. Artificial chemistry started as a method within the alife community to abstract the processes of chemical reactions.
  3. Evolutionary algorithms are a practical application of the weak alife principle applied to optimization problems. Many optimization algorithms have been crafted which borrow from or closely mirror alife techniques. The primary difference lies in explicitly defining the fitness of an agent by its ability to solve a problem, instead of its ability to find food, reproduce, or avoid death. The following is a list of evolutionary algorithms closely related to and used in alife:
  4. Multi-agent system – A multi-agent system is a computerized system composed of multiple interacting intelligent agents within an environment.
  5. Evolutionary art uses techniques and methods from artificial life to create new forms of art.
  6. Evolutionary music uses similar techniques, but applied to music instead of visual art.
  7. Abiogenesis and the origin of life sometimes employ alife methodologies as well.

Criticism

Alife has had a controversial history. John Maynard Smith criticized certain artificial life work in 1994 as "fact-free science".

National Labor Relations Board

From Wikipedia, the free encyclopedia
 
National Labor Relations Board
NLRB
National Labor Relations Board logo - color.jpg
Agency overview
FormedJuly 5, 1935; 85 years ago
Preceding agencies
JurisdictionFederal government of the United States
HeadquartersWashington, D.C.
Employees1,628 (2008)
Agency executives
Parent agencyExecutive Office of the President of the United States
Websitenlrb.gov

The National Labor Relations Board (NLRB) is an independent agency of the federal government of the United States with responsibilities for enforcing U.S. labor law in relation to collective bargaining and unfair labor practices. Under the National Labor Relations Act of 1935 it supervises elections for labor union representation and can investigate and remedy unfair labor practices. Unfair labor practices may involve union-related situations or instances of protected concerted activity. The NLRB is governed by a five-person board and a General Counsel, all of whom are appointed by the President with the consent of the Senate. Board members are appointed to five-year terms and the General Counsel is appointed to a four-year term. The General Counsel acts as a prosecutor and the Board acts as an appellate quasi-judicial body from decisions of administrative law judges.

The NLRB is headquartered at 1015 Half St. SE, Washington, D.C., with over 30 regional, sub-regional and residential offices throughout the United States.

History

1933–1935: First collective bargaining organization 'National Labor Board'

The history of the National Labor Relations Board (NLRB) can be traced to enactment of the National Industrial Recovery Act in 1933. Section 7(a) of the act protected collective bargaining rights for unions, but was difficult to enforce. A massive wave of union organizing was punctuated by employer and union violence, general strikes, and recognition strikes. The National Industrial Recovery Act was administered by the National Recovery Administration (NRA). At the outset, NRA Administrator Hugh S. Johnson believed that Section 7(a) would be self-enforcing, but the tremendous labor unrest proved him wrong. On August 5, 1933, President Franklin D. Roosevelt announced the establishment of the National Labor Board, under the auspices of the NRA, to implement the collective bargaining provisions of Section 7(a).

The National Labor Board (NLB) established a system of 20 regional boards to handle the immense caseload. Each regional board had a representative designated by local labor unions, local employers, and a "public" representative. All were unpaid. The public representative acted as the chair. The regional boards could hold hearings and propose settlements to disputes. Initially, they lacked authority to order representation elections, but this changed after Roosevelt issued additional executive orders on February 1 and February 23, 1934.

The NLB, too, proved ineffective. Congress passed Public Resolution No. 44 on June 19, 1934, which empowered the president to appoint a new labor board with authority to issue subpoenas, hold elections, and mediate labor disputes. On June 29, President Roosevelt abolished the NLB and in Executive Order 6763 established a new, three-member National Labor Relations Board.

Lloyd K. Garrison was the first Chairman of the National Labor Relations Board (often referred to by scholars the "First NLRB" or "Old NLRB"). The "First NLRB" established organizational structures which continue at the NLRB in the 21st century. This includes the regional structure of the board; the use of administrative law judges and regional hearing officers to initially rule on cases; an appeal process to the national board; and the use of expert staff, organized into various divisions, at the national level. Formally, Garrison established the:
  • Executive Office, which handled administrative activities of the national and regionalsit boards, field staff, and Legal Division. It was overseen by an Executive Secretary.
  • Examining Division, national staff which conducted field investigations and assisted the regional boards with adjudications, hearings, and representative elections.
  • Information Division, which provided the press and public with news.
  • Legal Division, which assisted the Department of Justice in seeking compliance with board decisions in the courts, or in responding to suits brought about by board decisions.
  • Research Division, which studied decisions of the regional boards so that a comprehensive labor law might be developed, and studied the economics of each case.
Within a year, however, most of the jurisdiction of the "First NLRB" was stripped away. Its decisions in the automobile, newspaper, textile, and steel industries proved so volatile that Roosevelt himself often removed these cases from the board's jurisdiction. Several federal court decisions further limited the board's power. Senator Robert F. Wagner (DNY) subsequently pushed legislation through Congress to give a statutory basis to federal labor policy that survived court scrutiny. On July 5, 1935, a new law—the National Labor Relations Act (NLRA, also known as the Wagner Act)—superseded the NIRA and established a new, long-lasting federal labor policy. The NLRA designated the National Labor Relations Board as the implementing agency.

1935–1939: Constitutionality, communism, and organizational changes

J. Warren Madden (left), Nathan Witt, and Charles Fahy (right) reviewing documents before a congressional hearing on December 13, 1937.

The first Chairman of the "new" NLRB was J. Warren Madden, professor of the University of Pittsburgh School of Law. Madden largely confirmed the previous structure of the "first NLRB" by formally establishing five divisions within the agency:
  • Administrative Division: Oversaw all administrative activities of national and regional boards and their finances; led by Secretary
  • Economic Division: Analyzed economic evidence in cases; made studies of economics of labor relations for use by board and courts; supervised by Chief Industrial Economist; also known as the Technical Service Division
  • Legal Division: Handled NLRB either decisions appealed to courts or cases in which NLRB sought enforcement of its decisions; overseen by General Counsel (hired by NLRB board); comprised two subdivisions:
    • Litigation Section: Advised national and regional boards, prepared briefs, worked with Justice Department
    • Review Section: Analyzed regional hearings and decisions; issued interpretations of law; prepared forms; drafted regulations
  • Publications Division: Handled all press and public inquiries; published decisions of national and regional boards and their rules and regulations; overseen by Director of Publications
  • Trial Examining Division: Held hearings before the national board; overseen by Chief Trial Examiner
Benedict Wolf served as first Secretary of the NLRB, Charles H. Fahy the first General Counsel, and David J. Saposs the first Chief Industrial Economist. Wolf resigned in mid-1937, and Nathan Witt, an attorney in the Legal Division, was named Secretary in October.

The Economic Division was a critical one for the NLRB. Cause-and-effect was one of the fundamental assumptions of the National Labor Relations Act, and for the causes of labor unrest to be understood economic analysis was needed. From the start, the Economic Division undertook three important tasks: 1) Gather economic data in support of cases before the courts; 2) Conduct general studies of labor relations to guide the board in formulating decisions and policies; and 3) Research the history of labor relations (the history of written agreements, whether certain issues were historically part of collective bargaining, how unions functioned internally, trends in employer activities, trends in collective bargaining, whether certain employer actions led to labor disputes, etc.) so that the board could educate itself, the courts, Congress, and the public about labor relations. The first function proved critical to the survival of the NLRB. It was the Economic Division's data and analysis, more than then NLRB's legal reasoning, which proved critical in persuading the Supreme Court to sustain the Wagner Act in NLRB v. Jones & Laughlin Steel. The Court even cited several Economic Division studies in its decision. In the wake of Jones & Laughlin Steel, many labor relations experts outside the agency concluded that economic analysis was "an accepted fact" essential to the proper functioning of the agency. The Economic Division did, too. It asked Madden to pair an economist with an attorney in every important case, and prepared outline of the economic data needed to support each case in case it went before the courts.

During his time on the NLRB, Madden was often opposed by the American Federation of Labor (AFL), which believed that Madden was using the NLRA and the procedures and staff of the NLRB to favor the AFL's primary competitor, the Congress of Industrial Organizations (CIO). The NLRB and NLRA were also under intense pressure from employers, the press, congressional Republicans, and conservative Democrats.

The NLRB's Economic Division proved critical in pushing for a congressional investigation into employer anti-union activities, and ensuring that investigation was a success. The Economic Division was deeply aware of employer use of labor spies, violence, and company unions to thwart union organizing, and quietly pressed for a congressional investigation into these and other tactics. Senator Robert M. La Follette, Jr. took up the suggestion, on June 6, 1936, the Senate Committee on Education and Labor established a Subcommittee Investigating Violations of Free Speech and the Rights of Labor chaired by La Follette. Better known as the "La Follette Committee", the subcommittee held extensive hearings for five years and published numerous reports. The committee uncovered extensive evidence of millions of company dollars used to pay for spies and fifth columnists within unions, exposed the culpability of local law enforcement in acts of violence and murder against union supporters (particularly in the Harlan County War), revealed the wide extent of illegal blacklisting of union members, and exposed the use of armed strikebreakers and widespread stockpiling of tear gas, vomit gas, machine guns, mortars, and armor by corporations to use against strikers. Some of the evidence the committee used was provided by the Economic Division, and the investigation proved critical for a time in defending the agency from business and congressional attack.

The biggest issue the NLRB faced was constitutional. The Justice Department and NLRB legal staff wanted the Supreme Court to rule as quickly as possible on the constitutionality of the NLRA. But the Board and Justice Department also realized that the Court's Lochner era legal philosophy made it unlikely for the Court to uphold the Act. Subsequently, Madden strove to resolve minor cases before they could become court challenges, and worked to delay appeals as long as possible until the best possible case could be brought to the Court. This legal strategy paid off. The Supreme Court upheld the NLRA in National Labor Relations Board v. Jones & Laughlin Steel Corporation, 301 U.S. 1 (1937). Afterward, Madden continued to strategically guide the NLRB's legal efforts to strengthen the federal courts' view of the NLRA and the board's actions. Because of the efforts of Madden and NLRB General Counsel Charles H. Fahy, the Supreme Court reviewed only 27 cases between August 1935 and March 1941, even though the board had processed nearly 5,000 cases since its inception. The Supreme Court enforced the NLRB's rulings in 19 cases without modifying them, enforced them with modification in six more, and denied enforcement in two cases. Additionally, the Board won all 30 injunction and all 16 representation cases before the lower courts, a rate of success unequalled by any other federal agency.

AFL opposition to the "Madden Board" grew after decisions in Shipowners' Ass'n of the Pacific Coast, 7 NLRB 1002 (1938), enf'd American Federation of Labor v. National Labor Relations Board, 308 U.S. 401 (1940) (awarding a longshoremen's unit to the CIO rather than the AFL), and American Can Co., 13 NLRB 1252 (1939) (unit's history of collective bargaining outweighs desire of workers to form craft-only unit).

The AFL began pushing for an investigation into the NLRB, and this investigation led to allegations of communist influence within the agency. In June 1938, the House Un-American Activities Committee (led by Chairman Martin Dies, Jr. [D-TX]) heard testimony from AFL leader John P. Frey, who accused Madden of staffing the NLRB with communists. The allegations were true, in at least one case: Nathan Witt, the NLRB's executive secretary and the man to whom Madden had delegated most administrative functions, was a member of the Communist Party of the United States. These allegations and discoveries significantly damaged the agency's support in Congress and with the public.

A second investigation into the NLRB led to organizational changes at the board. On July 20, 1939, Republicans and conservative Democrats formed a coalition to push through the House of Representatives a resolution establishing a Special Committee to Investigate the National Labor Relations Board (the "Smith Committee"), chaired by conservative, anti-labor Rep. Howard W. Smith (D-VA). On March 7, 1940, the Smith Committee proposed legislation to abolish the NLRB, reconstitute it, and radically amend the NLRA. President Roosevelt opposed the bill, although he conceded that perhaps the Board's membership should be expanded to five from three. The Smith bill won several early tests in the House, which also voted to substantially cut the NLRB's budget. Smith won a vote in the House Rules Committee permitting him to bring his bill to the floor for a vote. In an attempt to defuse the legislative crisis, Madden fired 53 staff and forced another five to resign, and decentralized the NLRB's trial process to give regional directors and field agents more authority. But the House still passed the Smith bill by a vote of 258 to 129 on June 7, 1940. To protect the NLRB, Roosevelt convinced Senator Elbert D. Thomas, Chairman of the Senate Committee on Education and Labor, to hold no hearings or votes on the bill, and the legislation died.

The Smith Committee investigation had a lasting effect on labor law in the U.S., and was the basis for the Taft-Hartley Act of 1947. Madden's term on the NLRB came to an end after just four years. On November 15, 1940, President Roosevelt nominated Harry A. Millis to the NLRB and named him Chairman, and nominated Madden to a seat on the U.S. Court of Claims.

1940–1945: The Economics Division and World War II

Another major structural change occurred at the same time that Madden left the NLRB. The Smith committee's anti-communist drive also targeted David J. Saposs, the NLRB Chief Industrial Economist. Saposs had been surreptitiously assessed by members of the Communist Party USA for membership, and rejected as a prospect. But Smith and others attacked Saposs as a communist, and Congress defunded his division and his job on October 11, 1940. Although the Smith committee's investigation proved critical, the disestablishment of the Economic Division was due to many reasons—both internal and external to the NLRB, and only some of which involved allegations of communist infiltration. As historian James A. Gross observed:
The Division was eliminated for all kinds of reasons which had nothing to do with the merits and importance of its work: political pressures and maneuverings, jealousy and empire building between and among lawyers and economists inside the Board, opposition to leftist ideologies, a personal attack on the Chief Economist, David Saposs, and a mighty hostility to the administrative process.
The loss of the Economic Division was a major blow to the NLRB. It had a major tactical impact: Economic data helped the NLRB fulfill its adjudicatorial and prosecutorial work in areas such as unfair labor practices (ULPs), representation elections, and in determining remedial actions (such as reinstatement, back pay awards, and fines). Economic data also undermined employer resistance to the agency by linking that opposition to employer ULPs. The loss also left the board dependent on the biased information offered by the parties in dispute before it, leading to poor decision-making and far less success in the courts. It also had a major strategic impact: It left the board unable to determine whether its administration of the law was effective or not. Nor could the board determine whether labor unrest was a serious threat to the economy or not. As labor historian Josiah Bartlett Lambert put it: "Without the Economic Research Division, the NLRB could not undertake empirical studies to determine the actual impact of secondary boycotts, jurisdictional strikes, national emergency strikes, and the like." The Economic Division was critical to a long-range NLRB process to lead to the long-term evolution of industrial labor relations in the U.S., but that goal had to be abandoned. Most importantly, however, the evisceration of the Economic Division struck at the fundamental purpose of federal labor law, which was to allow experts to adjudicate labor disputes rather than use a legal process. With this data and analysis, widespread skepticism about the board's expertise quickly spread through Congress and the courts. It also left the board largely unable to engage in rule-making, forcing it to make labor law on an inefficient, time-consuming case-by-case basis. As of 1981, NLRB was still the only federal agency forbidden to seek economic information about the impact of its activities.

The second Chairman of the NLRB, Harry A. Millis, led the board in a much more moderate direction. Lacking an economic division to give it ammunition to fight with Millis deliberately made the NLRB dependent on Congress and the executive branch for its survival. Millis made a large number of organizational changes. He stripped the office of Secretary of its power, set up an Administrative Division to supervise the 22 regional offices, initiated a study of the Board's administrative procedures, and genuinely delegated power to the regional offices. He removed casehandling and regional office communication from the jurisdiction of the Office of the Secretary and created a Field Division. He also adopted procedures requiring the board made its decisions based solely on the trial examiner's report, authorized NLRB review attorneys to review trial examiner report, required decisions to be drafted ahead of time and distributed for review, authorized review attorneys to revise drafts before a final decision was issued, required trial examiners to emphasize findings of fact and to address points of law, and began holding board meetings when there were differences of opinion over decisions.

Millis eliminated the Review Division's decisive role in cases, which had been established under Madden and Witt. Madden and Witt had adopted a highly centralized Board structure so that (generally speaking) only the cases most favorable to the board made it to the courts. The centralized structure meant that only the strongest cases made it to national board, so that the board could apply all its economic and legal powers to crafting the best decision possible. This strategy enabled the NLRB to defend itself very well before the Supreme Court. But Madden and Witt had held on to the centralized strategy too long, and made political enemies in the process. Millis substituted a decentralized process in which the board was less a decision-maker and more a provider of services to the regions. Many of the changes Millis instituted were designed to mimic requirements placed on other agencies by the Administrative Procedure Act.

American entry into World War II on December 8, 1941, significantly changed the NLRB. On January 12, 1942, President Roosevelt created the National War Labor Board (NWLB), which displaced the NLRB as the main focus of federal labor relations for the duration of the war. The NWLB was given the authority to "finally determine" any labor dispute which threatened to interrupt war production, and to stabilize union wages and benefits during the war. Although Roosevelt instructed the NWLB not to intrude on jurisdiction exercised by the NLRB, the War Labor Board refused to honor this request. From 1942 to 1945, Millis tried to secure a jurisdictional agreement with NWLB Chairman George W. Taylor. But these discussions proved fruitless, and Millis broke them off in June 1945. The NWLB also heavily raided the NLRB for staff, significantly hindering NLRB operations.

Additional changes came with the passage of the War Labor Disputes Act (WLDA) on June 25, 1943. Enacted over Roosevelt's veto after 400,000 coal miners, their wages significantly lower due to high wartime inflation, struck for a $2-a-day wage increase, the legislation (in part) required the NLRB to issue a ballot outlining all the collective bargaining proposals and counter-proposals, wait 30 days, and then hold a strike vote. The War Labor Disputes Act proved very burdensome. The NLRB processed 2,000 WLDA cases from 1943 to the end of 1945, of which 500 were strike votes. The act's strike vote procedures did little to stop strikes, however, and Millis feared unions were using the referendums to whip up pro-strike feelings among their members. Millis also believed the law's strike vote process permitted more strikes to occur than the NLRB would have allowed under its old procedures. There were so many strike vote filings in the six months after the war ended that NLRB actually shut down its long distance telephone lines, cancelled all out of town travel, suspended all public hearings, and suspended all other business to accommodate the workload. By early 1945, Millis was in ill health. He resigned from the NLRB on June 7, 1945, and Paul M. Herzog was named his successor.

1947–1965: Taft-Hartley

A major turning point in the history of the NLRB came in 1947 with passage of the Taft-Hartley Act. Disruptions caused by strikes during World War II as well as the huge wave of strikes that followed the end of the war fueled a growing movement in 1946 and 1947 to amend the NLRA to correct what critics saw as a pro-labor tilt in federal law. Drafted by the powerful Republican Senator Robert A. Taft and the strongly anti-union Representative Fred A. Hartley, Jr., the Taft-Hartley Act banned jurisdictional strikes, wildcat strikes, political strikes, secondary boycotts, secondary picketing, mass picketing, union campaign donations made from dues money, the closed shop, and unions of supervisors. The act also enumerated new employer rights, defined union-committed ULPs, gave states the right to opt out of federal labor law through right-to-work laws, required unions to give an 80-days' strike notice in all cases, established procedures for the President to end a strike in a national emergency, and required all union officials to sign an anti-Communist oath. Organizationally, the act made the General Counsel a presidential appointee, independent of the board itself, and gave the General Counsel limited powers to seek injunctions without referring to the Justice Department. It also banned the NLRB from engaging in any mediation or conciliation, and formally enshrined in law the ban on hiring personnel to do economic data collection or analysis.

In August 1947, Robert N. Denham became the NRLB's general counsel. He held "conservative views" and wielded "considerable influence" on labor-management relations and interpretations of the newly passed Taft-Hartley Act. In 1950, US President Harry S. Truman fired Denham (New York Times: "left at the behest of the President"). While NLRB general counsel, Denham received considerable news coverage as a "quasi-Republican." Nominated by US President Harry S. Truman, Denham received unanimous approval by the US Senate Labor Committee. He received "full and independent powers to investigate violations, file complaints and prosecute offenders before the board." In August 1947, he supported an "Anti-Red Affidavit Rule" and so sided with US Senator Robert A. Taft. In October 1947, the NRLB overruled him, which meant that top officers of the American Federation of Labor (AFL) and Congress of Industrial Organizations (CIO) would not have to sign an anti-Communist oath per the Taft-Hartley Act.

Herzog publicly admitted the need for some change in the NLRA, but privately he opposed the proposed Taft-Hartley amendments. He felt the communist oath provisions were unconstitutional, that the amendments would turn the NLRA into a management weapon, that creation of an independent General Counsel would weaken the NLRB, and that the law's dismantling of the agency's economic analysis unit deprived the NLRB of essential expertise. Nonetheless, Congress overrode Truman's veto of the Taft-Hartley Act on June 23, 1947, and the bill became law.

The Taft-Hartley Act fundamentally changed the nature of federal labor law, but it also seriously hindered the NLRB's ability to enforce the law. The loss of the mediation function left the NLRB unable to become involved in labor disputes, a function it had engaged in since its inception as the National Labor Board in 1933. This hindered the agency's efforts to study, analyze, and create bulwarks against bad-faith collective bargaining; reduced its ability to formulate national labor policy in this area; and left the agency making labor law on an ineffective, time-consuming case-by-case basis. The separation of the General Counsel from supervision by the national board also had significant impact on the agency. This separation was enacted against the advice of the Justice Department, contradicted the policy Congress had enacted in the Administrative Procedure Act of 1946, and ignored Millis' extensive internal reforms. The change left the NLRB as the only federal agency unable to coordinate its decision-making and legal activities, and the only agency exempted in this manner under the Administrative Procedure Act. The separation of the General Counsel was not discussed by the committee or by any witnesses during the legislation's mark-up. Indeed, there was no basis for it at all in the public record. It was, in the words of sociologist Robin Stryker, "little-noted" and "unprecedented".

The anti-communist oath provisions generated extensive public debate, and generated disputes before the Supreme Court several times. The Taft-Hartley oath first reached the court in American Communications Ass'n v. Douds, 339 U.S. 382 (1950), in which the court held 5-to-1 that the oath did not violate the First Amendment, was not an ex post facto law or bill of attainder in violation of Article One, Section 10, and was not a "test oath" in violation of Article Six. The issue again came before the court in Garner v. Board of Public Works, 341 U.S. 716 (1951), in which the court unanimously held that a municipal loyalty oath was not an ex post facto law or bill of attainder. It came before the court yet a third time in Wieman v. Updegraff, 344 U.S. 183 (1952). This time, the outcome was radically different. The Supreme Court unanimously ruled that state loyalty oath legislation violated the due process clause of the Fourteenth Amendment. In 1965, the Supreme Court held 5-to-4 that the anti-communist oath was a bill of attainder in United States v. Brown, 381 U.S. 437 (1965). The Supreme Court essentially overturned Douds, but did not formally do so.

1966–2007

The board itself (as an adjudicating body distinct from the functions separated as a result of Taft-Harley) has a fixed seating which is assigned based on the names of 5 original members.

2007–2013: Lack of quorum

From December 2007 until June 2010, the five-person Board had only two members, creating a legal controversy. Three members' terms expired in December 2007, leaving the NLRB with just two members—Chairman Wilma B. Liebman and Member Peter Schaumber. President George W. Bush refused to make some nominations to the Board and Senate Democrats refused to confirm those which he did make.

On December 28, 2007, just before the Board lost its quorum, the four members agreed to delegate their authority to a three-person panel per the National Labor Relations Act. Only Liebman and Schaumber remained on the Board, but the Board concluded that the two constituted a quorum of the three-person panel and thus could make decisions on behalf of the Board. Liebman and Schaumber informally agreed to decide only those cases which were in their view noncontroversial and on which they could agree, and issued almost 400 decisions between January 2008 and September 2009.

The U.S. Courts of Appeals for the First, Second, and Seventh Circuits upheld the two-member NLRB's authority to decide cases, while the D.C. Circuit Court of Appeals did not. In September 2009, the Justice Department asked the U.S. Supreme Court to immediately hear arguments concerning the dispute, given the high stakes involved. The Supreme Court granted certiorari in October and agreed to decide the issue.

In June 2010, the Supreme Court ruled in New Process Steel, L. P. v. NLRB that the two-member Board had no authority to issue decisions, invalidating all rulings made by Liebman and Schaumber. In 2013, the question of a legitimate quorum on the NLRB surfaced again, when the United States Court of Appeals for the District of Columbia Circuit ruled that President Obama had "violated the Constitution when he bypassed the Senate to fill three board vacancies".

Structure

Plaque on the exterior of 1099 14th Street NW in Washington, D.C., the NLRB headquarters as of 2013.
 
Union members picketing NLRB rulings outside the agency's Washington, D.C., headquarters in November 2007.
 
In 1947, the Taft–Hartley Act created a formal administrative distinction between the Board and the General Counsel of the NLRB. In broad terms, the General Counsel is responsible for investigating and prosecuting unfair labor practice claims and for the general supervision of the NLRB field offices. The General Counsel is appointed by the President to a four-year term and independent from the Board; it has limited independence to argue for a change in the law in presenting cases to the Board. The General Counsel oversees four divisions: the Division of Operations Management, the Division of Administration, the Division of Advice, and the Division of Enforcement Litigation.

The Board, on the other hand, is the adjudicative body that decides the unfair labor practice cases brought to it. Once the Board has decided the issue, it is the General Counsel's responsibility to uphold the Board's decision, even if it is contrary to the position it advocated when presenting the case to the Board. The Board is also responsible for the administration of the Act's provisions governing the holding of elections and resolution of jurisdictional disputes.

The Board has more than thirty regional offices. The regional offices conduct elections, investigate unfair labor practice charges, and make the initial determination on those charges (whether to dismiss, settle, or issue complaints). The Board has jurisdiction to hold elections and prosecute violations of the Act in Puerto Rico and American Samoa.

Jurisdiction

The Board's jurisdiction is limited to private sector employees and the United States Postal Service; other than Postal Service employees, it has no authority over labor relations disputes involving governmental, railroad and airline employees covered by the Adamson Railway Labor Act, or agricultural employees. On the other hand, in those parts of the private sector its jurisdictional standards are low enough to reach almost all employers whose business has any appreciable impact on interstate commerce.

Processing of charges

Charges are filed by parties against unions or employers with the appropriate regional office. The regional office will investigate the complaint. If a violation is believed to exist, the region will take the case before an Administrative Law Judge who will conduct a hearing. The decision of the Administrative Law Judge may be reviewed by the five member Board. Board decisions are reviewable by United States Courts of Appeals. The Board's decisions are not self-executing: it must seek court enforcement in order to force a recalcitrant party to comply with its orders.

General Counsel

Lafe Solomon was named Acting General Counsel on June 21, 2010. His nomination was sent to the U.S. Senate on January 5, 2011. Solomon's authority came into question on August 13, 2013 when Judge Benjamin Settle for the United States District Court for the Western District of Washington denied a petition for injunctive relief, ruling that Solomon had not been properly appointed under the Federal Vacancies Reform Act of 1998 (FVRA). Although other district courts had enforced Solomon's requests, Judge Settle's decision called into question all of Solomon's activity since June 21, 2010, focusing on subsections (a)(1) and (2) of the FVRA; some pundits claimed that Solomon's appointment was allowed under subsection (a)(3). President Obama withdrew Solomon's nomination.
On July 31, 2013, President Obama nominated former NLRB nominee Richard Griffin as General Counsel—"a kind of prosecutor at the board" and "one of the most critical roles at the agency." Solomon's nomination was withdrawn. The Senate approved Griffin's nomination on October 29, 2013, by a vote of 55 to 44.

2007–2013: Unoccupied board seats

In April 2009, President Obama nominated Craig Becker (Associate General Counsel of the Service Employees International Union), Mark Gaston Pearce (a member on the Industrial Board of Appeals, an agency of the New York State Department of Labor), and Brian Hayes (Republican Labor Policy Director for the Senate Committee on Health, Education, Labor and Pensions) to fill the three empty seats on the NLRB.

Becker's nomination appeared to fail on February 8, 2010, after Republican Senators (led by John McCain) threatened to filibuster his nomination. President Obama said he would consider making recess appointments to the NLRB due to the Senate's failure to move on any of the three nominations. On March 27, 2010, Obama recess appointed Becker and Pearce.

On June 22, 2010, a voice vote in the Senate confirmed Pearce to a full term, allowing him to serve until August 27, 2013. The same day, the Senate confirmed Republican nominee Brian Hayes of Massachusetts by voice vote. Hayes' term ended on December 16, 2012. Becker's term, as a recess appointee, ended on December 31, 2011. Effective August 28, 2011, Pearce was named Chairman to replace Democrat Wilma Liebman, whose term had expired.

On January 4, 2012, Obama announced recess appointments to three seats on the board: Sharon Block, Terence F. Flynn, and Richard Griffin. The appointments were criticized by Republicans, including the House Speaker John Boehner, as unconstitutional and "a brazen attempt to undercut the role of the Senate to advise and consent the executive branch on appointments". Although made as recess appointments, critics questioned their legality, arguing that Congress had not officially been in recess as pro forma sessions had been held. Former U.S. attorney general Edwin Meese stated that in his opinion, since the appointments were made when the Senate was "demonstrably not in recess" they represented "a constitutional abuse of a high order". On January 12, 2012 the U.S. Justice Department released a memo stating that appointments made during pro forma sessions are supported by the Constitution and precedent.

On January 25, 2013, in Noel Canning v. NLRB, a panel of the U.S. Court of Appeals for the District of Columbia Circuit ruled that President Obama's recess appointments were invalid as they were not made during an intersession recess of the Senate, and the President moved to fill them during the same recess. On May 16, 2013, in National Labor Relations Board v. New Vista Nursing and Rehabilitation, the U.S. Court of Appeals for the Third Circuit became the second federal appellate court to rule that the recess appointments to the NLRB were unconstitutional. In a split decision, it also found that the March 27, 2010 recess appointment of Craig Becker was unconstitutional. On January 14, 2014, the U.S. Supreme Court heard the case in National Labor Relations Board v. Noel Canning.

Between January 2008 and mid-July 2013 the agency never had all five members, and not once did it operate with three confirmed members. On July 14, 2013, Senate Majority Leader Harry Reid threatened to exercise the "nuclear option" and allow a simple majority (rather than a supermajority) of the Senate to end a filibuster. This threat to end the filibuster's privileged position in the Senate was intended to end Republican filibustering of NLRB nominees. On July 16, 2013, President Obama and Senate Republicans reached an agreement to end the impasse over NLRB appointees. Obama withdrew the pending nominations of Block and Griffin, and submit two new nominees: Nancy Schiffer, associate general counsel at the AFL-CIO, and Kent Hirozawa, chief counsel to NLRB Chairman Mark Gaston Pearce. Republicans agreed not to oppose a fourth nominee, to be submitted in 2014.

On July 30, 2013, the Senate confirmed all five of Obama's nominees for the NLRB: Kent Hirozawa, Harry I. Johnson III, Philip A. Miscimarra, Mark Gaston Pearce and Nancy Schiffer. Johnson and Miscimarra represented the Republican nominees for the board. Pearce was confirmed for a second five-year term. Nancy Schiffer's term ended on December 15, 2014. She was succeeded by Lauren McFerran on December 16, 2014. Harry I. Johnson III's term ended on August 27, 2015.

2017 appointments

On January 25, 2017, President Donald Trump appointed Philip Miscimarra the acting Chairman of the NLRB. Miscimarra's term expired on December 16, 2017. Marvin Kaplan succeeded him as NLRB Chairman on December 21, 2017. Kaplan was replaced as Chairman in April 2018 by John F. Ring, who currently holds that position.

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