Twitter is officially on the road to a stock market debut, and funds that already own stakes in the social media company are enjoying the ride.

Shares of GSV Capital (GSVC), a publicly traded fund that invests in "high growth" private companies, rallied almost 13% Friday. GSV said it holds 1.9 million shares of Twitter as of June 30. Twitter is the fund's biggest holding, at 15% of the total portfolio.

Similarly, Twitter is also the biggest holding in the Firsthand Technology Value Fund (SVVC). With just over 1 million shares of the social media platform, Twitter represents nearly 11% of the total portfolio as of mid-year. Shares of Firsthand Technology Value jumped more than 6% Friday.

Both funds, which owned Facebook (FB) prior to its market debut and remain invested in that company, ran up significantly last year before Facebook's highly anticipated IPO. Both tumbled in the aftermath of Facebook's botched debut on the Nasdaq. But the funds have rebounded recently thanks to the recovery in Facebook's stock.

GSV Capital is up nearly 60% this year, while Firsthand Technology Value Fund is up almost 40%.

Related: Twitter IPO will come sooner than you think

According to data from Morningstar, nutual fund giant T. Rowe Price (TROW), which began investing in Twitter in 2009, has shares of the company in several of its own mutual funds as well as funds on which it serves as a subadviser.

Twitter's upcoming IPO could also be a boon for the Global X Social Media ETF (SOCL), which will likely be the first exchange-traded fund to add Twitter -- as early as five days after it begins trading. The ETF, which holds Facebook, LinkedIn (LNKD), Groupon (GRPN), Pandora (P) and other social media stocks, was the first ETF to add Facebook after it went public. The fund is up almost 50% in 2013.

Twitter has been rumored to go public for the past few years, but on Thursday the company made it official. In a tweet -- of course -- the company said it has filed for a confidential IPO with the Securities and Exchange Commission.

Taking advantage of new regulations in the Jumpstart Our Business Startups (JOBS) Act, Twitter was able to complete its filing without divulging any financial information yet. Under the act, companies with less than $1 billion of annual revenue can keep those details out of the public eye until a later date.