7. Arnel, a 55-year-old seafarer who worked on board different foreign vessels, went to the office of the Social Security System (SSS) to avail of his retirement benefits. However, he found out that his contributions had not been paid by his principal employer, Pancho Lines (PL). When Arnel demanded an explanation from PL, the latter replied that it was not obligated to cover his SSS membership since he was hired abroad and covered by another insurance provider. Is PL correct? Discuss your answer.