What happened

Shares of special purpose acquisition company (SPAC) Social Capital Hedosophia Holdings II (IPOB) are up 12.5% as of 3:40 p.m. EST. Social Capital Hedosophia Holdings may not hold onto all of those gains much longer, but Opendoor might.

So what

This morning, shareholders of the SPAC voted to approve its acquisition of "iBuying" specialist Opendoor Labs in a deal that will probably close tomorrow. (iBuying is basically the process of using algorithms to determine the value of a piece of real estate and buying it sight unseen.)

Arrow angles up on a green stock chart

Image source: Getty Images.

After the transaction closes Friday, Opendoor will IPO in a reverse merger into already-listed Social Capital Hedosophia Holdings, and shift its shares over to the Nasdaq. It will begin trading on Monday, Dec. 21, under the name Opendoor Technologies, and with a new ticker symbol, OPEN.  

Now what

Today's shareholder vote approving the merger was the final hoop Social Capital Hedosophia Holdings had to jump through to complete the taking public of its new prize. Investors are rushing to get in, therefore, on what is essentially a done deal, in anticipation that once Opendoor becomes investable under its own more recognizable name, the shares will pop next week.

Start your stopwatches. In three days, we'll find out if they were right to do so -- or if they jumped the gun.