http://www.reuters.com/article/us-gm-lyft-investment-idUSKBN...
http://www.reuters.com/article/us-gm-lyft-investment-idUSKBN...
Lyft with the funding from GM has only raised $2B over it's lifespan which is comparable to that of Uber. Uber has raised nearly $13B and blown through most of it.
At their last round, Lyft is valued at about $6B and Uber is valued at $68B. One of these is reasonable based on the taxi market size (domestic $20B), the other is about 2x over the assumed value with decent market share and margins it could attain.
The only way for Uber to express the value on the books is to replace car ownership, which is unlikely with the turnover rate of individuals replacing their cars, they'll need about a decade or more runway to justify the current valuation.
Lyft and GM have an advantage in the race to replace ownership, with their partnership. Lyft gets a partner that can reduce cost of vehicle supply costs and maintenance, while GM gets a hedge against a possible headwind to their current business model.
It's a bit of a chicken and the egg, because it's absolutely related to their valuation. That valuation is based on a flaw somewhere in their model potential, which feeds back into the model of potential (via expressing oversized outside interest).
And Box had a small downward valuation shift (-36%, -$0.9B), between last raised valuation and IPO.
Uber's numbers even giving them liberal growth potential of 500% places them at around $33.75B (-50% current value, -$34B).
FB's valuation at IPO was still smaller than it's primary domestic market's (ad spending) size ($165B in 2012).
Uber's primary domestic market (taxis) is only valued at ($20B), so if they captured all of the US taxi, their current valuation requires them to capture over 300% of the market.^
Now obviously that's not a perfect barometer. There are other variables and adjustments to make, but it makes it very clear that there is limited upside potential. Without claiming another market (ownership), it's actually damn near impossible. They've also ceded competition in the Chinese market to DiDi, so they can't make it up via global expansion either.
^edit (Obviously, this is a 1x multiple, as you increase to more reasonable values it drops the share required, but you have to push it pretty hard to reduce market share to a decent level.)