Whether Facebook will suffer legal consequences from its recent mishap is a different matter. In litigation arising out of an earlier breach, In re Facebook Inc. Consumer Privacy User Profile Litigation, No. 3:18-MD-02843 (N.D. Cal.), Facebook recently (Nov. 2) filed a motion to dismiss that raises a host of colorable defenses, including lack of cognizable injury, consent, and waiver.
The legal landscape, though, will soon be changing. California has passed a Consumer Privacy Act that goes into effect in 2020, and, while applicable only to California residents, it of course has to be taken seriously by data-collecting companies due to California's large population. The law (A. B. 375, codified at Title 1.81.5, Sec. 1798.100ff.) provides that California consumers will have the right to request that a company delete their personal information, and personal information is broadly defined to include, among other items, geographic location, internet browsing history, and "inferences" that a company draws based on the consumer's information to create a profile of the consumer (Sec. 1798.140(o)(F), (G), (K)). The Act also requires that companies maintain "reasonable security procedures" (Sec. 1798.156(a)).
The most interesting -- and from an industry standpoint, threatening -- provision is the requirement that personal information be kept in a "readily usable format" that users can port to an alternative service provider (Sec. 1798.100(d)). Basically, the law requires a data-collecting company to share with direct competitors its means of organizing and exploiting consumer data. The portability requirement is therefore a threat to the business model because the proprietary data mining work that the company has accomplished on its users for its own commercial purposes -- i.e., for being able to target specific ads to specific users -- can end up in the hands of a competitor, which dilutes the competitive advantage of assembling such information in the first place.
There is also speculation that a California-type privacy law will be proposed in the new Congress, which would put even more pressure on the business model of data-collecting companies, although nothing concrete is on the table at the moment.