2nd article just links to other articles on fortune which don't have anything to back them up.
So I'd be dubious of those figures.
"Y-Combinator’s success is undeniable: the program has produced 37 start-ups worth over $40 million each in the past five years. In its first six years, 72 percent of Y.C.’s 249 start-ups raised money after Demo Day, and today, the average value of a Y.C.-financed start-up is $22.4 million. However, these statistics also reveal a grimmer reality: 93 percent of the 511 companies accepted by Y-Combinator have failed. Even more alarming, only 3 to 5 percent of the companies that apply to Y-Combinator are even accepted, meaning that only one in every 200 companies that applies to Y.C. eventually succeeds."
Emphasis mine.
[+] http://koltai.co/notebook/the-risky-business-of-entrepreneur...
EDIT: Please disregard this post. Left for historical purposes. sama notes that the stats are inaccurate.
EDIT 2: The citations in that link I mention above are from nytimes and business insider. They might be accurate, if a bit old, but require verification. Treat them appropriately.
Also, he average valuation of all YC startups through w2014 (i.e. with enough time to have raised a first round) is now over $100MM.
- cofounder disputes - market timing - not continuing to find growth
are top 3
Dropbox - Not public, probably not profitable
Airbnb - Not public, might be profitable, lots of legal questions.
Coinbase - Not public, raised $100m+, no idea if it's profitable
Stripe - Not public, raised almost $200m, almost certainly not profitable
Reddit - Acquired by Conde Nast (private), might be profitable.
Zenefits - Not public, probably not profitable, raised ~$500m
Instacart - Not public, not profitable, raised ~$300m
Weebly - Not public, might be profitable
So I'd say their track record isn't great on that front. I don't know of any meaningful ($1bn+) IPOs of YC companies (not to say that they don't exist). The fact that I had no idea what Weebly was until a moment ago probably means it's not one of their success stories. I suspect DropBox will IPO at some point, but after Box's IPO, they have an uphill battle to prove that they won't be the same dud. Coinbase I had forgotten existed, so I'm really curious what their deal is (especially considering their valuation is so high, I wonder if they can support it anymore).
Box is trading at about 6x their forward revenue in valuation, versus cloud industry's 10-12x average, and during the last Dropbox round it was rumored it was valued at 40X its forward revenue.
Meanwhile Box is winning major partnerships and customers left and right and the market still hates it, I really wonder how Dropbox is gonna tell their story considering their vast consumer user base is a liability instead of asset when it comes to profitability.
But how many were successful, in the sense of paying back their investors? The most likely outcome of most VC investments is a "zombie", a company which can pay its own operating systems but is a net loss to investors. The usual VC stats are that about 10% are wins, 20% go bankrupt, and the rest drag on for years in zombie mode.