Listening to Ben Silbermann, CEO of Pinterest – a company now valued at at an astounding $11 billion – it was hard not to feel that investing in tech startups has gotten overheated. Silbermann said that while his site is focusing on ways to turn its popular pin pages into revenue, he has no plans for an IPO because public companies need to have predictable revenues. Pinterest does not.

But Kravis provided a venture capitalist’s view of the tech investing frenzy. When was asked by my colleague Dan Primack if he would invest in a fund of Unicorns that included the roughly 100 start-ups now valued at over a billion dollars, he suggested he might. Why? Because while most will never live up to those high valuations, just one might. And if that one proves to be the next Facebook, it would justify the investment.

Meanwhile, Hillary Clinton injected Unicorns into the political debate yesterday, suggesting “sharing economy” companies like Uber, Lyft, and Airbnb – weren’t providing sufficient protections for those who worked for them. Expect to hear more on this theme in the months ahead. Technology companies have clearly created new opportunities for workers, but they are just as clearly putting downward pressure on pay and benefits – a central issue for the upcoming political season.

Top News

• Iran reaches nuclear agreement

Iran and half a dozen world powers have sealed a historic deal to curb the Islamic Republic's nuclear program in return for ending sanctions, which caps two years of tough diplomacy with the biggest breakthrough in relations in decades. What does this deal mean to the world's economy? If approved by the U.S. Congress, it could enable to the nation to ramp up energy exports and open its doors to international investors. Bloomberg

• Hillary Clinton not a fan of sharing

The sharing economy has found a new opponent – Democratic presidential candidate Hillary Clinton. In her first major economic policy speech on Monday that highlighted a push for higher wages, Clinton said that while start-ups have helped Americans make more money renting out rooms or driving their own car, she said it raised questions about workplace protections and what a good job will look like in the future. Fortune

• Micron could be a takeover target

The biggest microchip company in China, Tsinhgua Unigroup Ltd., is preparing a $23 billion bid for memory chip maker Micron, the Wall Street Journal reported. If the deal were to occur, it would be the largest ever acquisition of a U.S. company by a Chinese one, vastly more expensive than the $7.1 billion purchase of Smithfield Foods. Fortune

• Greece could be forced to sell islands

One aspect of the bailout deal for Greece that should have received more attention is this: the nation's government promised to sell billions of dollars of "valuable Greek assets." That could result in Athens actually auctioning off Greek islands, nature preserves or even ancient ruins. "This is an idea to humiliate Greeks," said a Greek strategist and adviser. Time

• Asian aviation boom has risks

An analysis of flight data and interviews with aviation experts and pilots has indicated that airline snafus are going unreported in the fast-growing Asian aviation market. And experts say that without proper accounting, airlines can't learn from mistakes and botched procedures are left to become a bigger endemic. WSJ (subscription required)

Around the Water Cooler

• Unicorns: Proceed with caution

Private equity veteran Henry Kravis, speaking at Fortune's Brainstorm Tech conference, says startups shouldn't plan to go public unless they have a really good reason to raise the money. And in the current environment, where it is fairly easy to raise cash while remaining private, Kravis said he would advise them from exposing themselves to Wall Street scrutiny too soon. "I think the worst thing to happen to corporate America is quarterly earnings," said Kravis. Fortune

• Retailer rivalries heat up in July

The war in the retail world between Walmart and Amazon.com is escalating in July – yes the middle of the summer, not during the key holiday shopping season. Both are holding massive, Black Friday-style sales evens this upcoming Wednesday, with Walmart taking aim at Amazon for only making its deal available for those that pay $99 annually to subscribe to Amazon Prime. Amazon then accused Walmart of charging different prices in various stores and online. Fortune

• Will "clawbacks" work?

The Securities and Exchange Commission is mulling the idea of adopting programs that would enable a "claw back" – or recovery – of compensation to all publicly traded firms. That news has already been reported, but Andrew Ross Sorkin points out it could backfire. The new law could drive up base salaries, or even increase incentive pay even higher to account for risk of a potential clawback. And companies could opt not to pursue a clawback if the costs to do so could exceed the amount to be recovered. New York Times