Facebook has filed to establish FB PAC, a political action committee intended to “give [Facebook's] employees a way to make their voice heard in the political process,” presumably over and above voting and contributing independently to campaigns and other PACs.
The company has spent about a million dollars lobbying over the last three years, according to Senate records and documented by OpenSecrets, with the sum spent increasing every year. For comparison, Microsoft spent around $9m per year through its own PAC at its peak, though that number has gone down to about a third of that now. Establishing a PAC will enable Facebook to make direct contributions to candidates and parties, and if it chooses, spend unlimited sums bankrolling secondary efforts like independent ad campaigns.
We can’t be too sure exactly who or what FB PAC will support, but its spending so far has been significantly concentrated in industry-related issues such as internet privacy, foreign regulations on internet access, and of course weighing in on copyright questions, which would directly affect its business. You can read their official spending report here (PDF). The theoretical spending cap for PACs is several million dollars ($5000 per candidate per race and some miscellaneous allowances), so there’s plenty of room for them to grow into.
Let’s not let partisan politics creep into this too much. Forming a PAC is mainly just another way for Facebook to make its presence felt in American politics, a natural tendency in large organizations. Participating in public politics can be a polarizing choice, though, and it may be that Facebook, being as it is a conglomeration of many differing political groups and philosophies, may have some fancy footwork to do in the future to keep its campaign contributions from riling its user base.
So far they have only filed the paperwork and formalized their intentions. FBPAC.us and FBPAC.org are registered but empty as of this writing.
Note: Microsoft reports and tracks its contributions and lobbying expenses differently from OpenSecrets. I chose the latter’s numbers for consistency purposes.