P.R. Laws tit. 29, § 281
It is hereby declared that the additional compensation on the basis of double time fixed by §§ 271—288 of this title for extra hours of work may not be waived.
Any clause or stipulation by virtue of which the employee agrees to waive the payment of the additional compensation for extra hours fixed by §§ 271—288 of this title shall be null.
No judgment, award, adjudication or any other provision of a claim for compensation, right or benefit under any act, mandatory decree, wage order, collective agreement or work contract, may be raised as a defense of a former adjudication by [the] fractioning of cause of action, to defeat another claim, unless the same cause of action has been expressly adjudicated in the previous proceeding, for the same facts between the same parties.
History —May 15, 1948, No. 379, p. 1254, § 12; June 5, 1973, No. 95, p. 408; renumbered as § 13 on July 20, 1995, No. 83, § 5.