1974—Subsec. (d). Pub. L. 93–360, § 1(c), (d), substituted “any notice” for “the sixty-day” and inserted “, or who engages in any strike within the appropriate period specified in subsection (g) of this section,” in loss-of-employee-status provision and inserted enumeration of modifications to this subsection which are to be applied whenever the collective bargaining involves employees of a health care institution.

Subsec. (g). Pub. L. 93–360, § 1(e), added subsec. (g).

1959—Subsec. (a)(3). Pub. L. 86–257, § 201(e), struck out “and has at the time the agreement was made or within the preceding twelve months received from the Board a notice of compliance with sections 159(f), (g), (h) of this title” after “such agreement when made” in cl. (i).

Subsec. (b)(4). Pub. L. 86–257, § 704(a), among other changes, substituted “induce or encourage any individual employed by any person engaged in commerce or in an industry affecting commerce to engage in, a strike or a refusal in the course of his employment” for “induce or encourage the employees of any employer to engage in, a strike or a concerted refusal in the course of their employment” in cl. (i), added cl. (ii), and inserted provisions relating to agreements prohibited by subsection (e) of this section in cl. (A), the proviso relating to primary strikes and primary picketing in cl. (B), and the last proviso relating to publicity.

Subsec. (b)(7). Pub. L. 86–257, § 704(c), added par. (7).

Subsec. (e). Pub. L. 86–257, § 704(b), added subsec. (e).

Subsec. (f). Pub. L. 86–257, § 705(a), added subsec. (f).

1951—Subsec. (a)(3). Act Oct. 22, 1951, substituted “and has at the time the agreement was made or within the preceding twelve months received from the Board a notice of compliance with section 159(f), (g), (h) of this title, and (ii) unless following an election held as provided in section 159(e) of this title within one year preceding the effective date of such agreement, the Board shall have certified that at least a majority of the employees eligible to vote in such election have voted to rescind the authority of such labor organization to make such an agreement:” for “; and (ii) if, following the most recent election held as provided in section 159(e) of this title the Board shall have certified that at least a majority of the employees eligible to vote in such election have voted to authorize such labor organization to make such an agreement:”.

1947—Act June 23, 1947, amended section generally by stating what were unfair labor practices by a union as well as by an employer, and by inserting provisions protecting the right of free speech for both employers and unions.

Amendment by Pub. L. 93–360 effective on thirtieth day after July 26, 1974, see section 4 of Pub. L. 93–360, set out as an Effective Date note under section 169 of this title.

Amendment by sections 704(a)–(c) and 705(a) of Pub. L. 86–257 effective sixty days after Sept. 14, 1959, see section 707 of Pub. L. 86–257, set out as a note under section 153 of this title.

For effective date of amendment by act June 23, 1947, see section 104 of act June 23, 1947, set out as a note under section 151 of this title.

Section 705(b) of Pub. L. 86–257 provided that: “Nothing contained in the amendment made by subsection (a) [amending this section] shall be construed as authorizing the execution or application of agreements requiring membership in a labor organization as a condition of employment in any State or Territory in which such execution or application is prohibited by State or Territorial Law.”

Act June 23, 1947, ch. 120, title I, § 102, 61 Stat. 152, provided that: “No provision of this title [amending this subchapter] shall be deemed to make an unfair labor practice any act which was performed prior to the date of the enactment of this act [June 23, 1947] which did not constitute an unfair labor practice prior thereto, and the provisions of section 8(a)(3) and section 8(b)(2) of the National Labor Relations Act as amended by this title [subsecs. (a)(3) and (b)(2) of this section] shall not make an unfair labor practice the performance of any obligation under a collective-bargaining agreement entered into prior to the date of the enactment of this Act [June 23, 1947], or (in the case of an agreement for a period of not more than one year) entered into on or after such date of enactment, but prior to the effective date of this title, if the performance of such obligation would not have constituted an unfair labor practice under section 8(3) [see subsec. (a)(3) of this section] of the National Labor Relations Act prior to the effective date of this title [sixty days after June 23, 1947] unless such agreement was renewed or extended subsequent thereto.”