Facebook Confirms It Will Sponsor Trump's Republican National Convention
fortune.com
fortune.com
I can't seem to find any information about how the Democratic convention is being funded this year, but in 2012 they specifically rejected corporate funding [0]. Not sure if that was a one-time thing or meant to be an enduring policy.
Also, boo on Forbes for calling it "Trump's Republican National Convention" in the headline. It's run by the party, not the candidate, and there's currently a lot of contention between Trump and the convention leadership [1] so calling it his is a little misleading.
[0] http://thecaucus.blogs.nytimes.com/2011/02/04/no-corporate-m... [1] http://www.nytimes.com/2016/05/09/us/politics/donald-trumps-...
Formally, just as it is formally where the nominee for President is chosen. In reality, this usually happens (and is announced) prior to the convention.
> and the party platform for that year is drafted.
Arguably, the party platform is largely irrelevant, since there is no accountability to it, and individual candidates own campaigns (including the Presidential ticket) establish their own effective campaign platform (which usually doesn't take the form of a single formal document, but is presented through individual issue papers, the campaign website, stump speeches, etc.), which can be very different from what is in the party document.