Section 10 of Republic Act No. 8042 (Migrant Workers Act) provides for money claims in cases of unjust termination of employment contracts:
In case of termination of overseas employment without just, valid or authorized cause as defined by law or contract, the workers shall be entitled to the full reimbursement of his placement fee with interest of twelve percent (12%) per annum, plus his salaries for the unexpired portion of his employment contract or for three (3) months for every year of the unexpired term, whichever is less.
The Migrant Workers Act provides that salaries for the unexpired portion of the employment contract or three (3) months for every year of the unexpired term, whichever is less, shall be awarded to the overseas Filipino worker, in cases of illegal dismissal. However, in 24 March 2009, Serrano v. Gallant Maritime Services and Marlow Navigation Co. Inc.,58 the Court, in an En Banc Decision, declared unconstitutional the clause “or for three months for every year of the unexpired term, whichever is less” and awarded the entire unexpired portion of the employment contract to the overseas Filipino worker.
On 8 March 2010, however, Section 7 of Republic Act No. 10022 (RA 10022) amended Section 10 of the Migrant Workers Act, and once again reiterated the provision of awarding the unexpired portion of the employment contract or three (3) months for every year of the unexpired term, whichever is less.
Nevertheless, since the termination occurred on January 1999 before the passage of the amendatory RA 10022, we shall apply RA 8042, as unamended, without touching on the constitutionality of Section 7 of RA 10022.
The declaration in March 2009 of the unconstitutionality of the clause “or for three months for every year of the unexpired term, whichever is less” in RA 8042 shall be given retroactive effect to the termination that occurred in January 1999 because an unconstitutional clause in the law confers no rights, imposes no duties and affords no protection. The unconstitutional provision is inoperative, as if it was not passed into law at all.59
http://sc.judiciary.gov.ph/jurisprudence/2012/february2012/175558.html