Apple threatened to remove Facebook’s products from its App Store, after the BBC found domestic “slaves” for sale on apps, including Instagram, in 2019.
The threat was revealed in the Wall Street Journal’s (WSJ) Facebook Files, a series of reports based on its viewing of internal Facebook documents.
Facebook says it prohibits human exploitation “in no uncertain terms”.
It says it has been “combating human trafficking on our platform for many years”.
The firm added: “Our goal remains to prevent anyone who seeks to exploit others from having a home on our platform.”
The BBC News Arabic investigation exposed a booming online black market in the illegal buying and selling of domestic workers.
It shed light on a world in which women endured a life of servitude and were kept behind closed doors, deprived of their basic rights, unable to leave and at risk of being sold to the highest bidder. Experts said these conditions amounted to slavery.
The trade was carried out using a number of apps including Facebook-owned Instagram.
The posts and hashtags used for sales were mainly in Arabic, and shared by users in Saudi Arabia and Kuwait.
The women were often categorised by race, and available to buy for a few thousand dollars.
The WSJ reported that following the BBC investigation, Apple told Facebook to do more to tackle human trafficking.
It said the social media giant only took “limited action” until “Apple Inc. threatened to remove Facebook’s products from the App Store, unless it cracked down on the practice”.
The BBC has approached Apple about the claim.
The paper also quoted a 2019 internal report from Facebook, suggesting that the social media giant knew about, and had been investigating, the online slave trade before the BBC got in contact.
In the report, a Facebook researcher writes: “Was this issue known to Facebook before BBC inquiry and Apple escalation?
“Yes. Throughout 2018 and [the first half of] 2019 we conducted the global Understanding Exercise in order to fully understand how domestic servitude manifests on our platform across its entire life cycle: recruitment, facilitation, and exploitation.”