Mizuho Securities analyst Haendel St. Juste downgraded both KB Home (KBH - Get Report) and PulteGroup (PHM - Get Report) to "underperform" from "neutral" on concerns that full valuations will make it harder for the homebuilders to outperform, Barron's reported.

St. Juste put a $21 price target on KB Home despite "substantial improvement in gross margins." There's more optimism than there should be and lagging orders paired with a low community count mean limited upside, St. Juste wrote.

Pulte got a $22 price target but the lack of expected margin growth and negative absorption rates suggest Pulte's current valuation is "unjustified," according to St. Juste.

St. Juste's two buy-rated stocks in the homebuilder sector are Lennar Corp (LEN - Get Report) and Toll Brothers Inc (TOL - Get Report) .

KB Home and Pulte traded down at midday.

What's Hot On TheStreet

Tesla's Model 3 is born: Tesla (TSLA - Get Report) CEO Elon Musk tweeted photos of the first Model 3 ever produced, which appears to be black, in the evening on Saturday. The car is going straight to Musk's garage. "Ira Ehrenpreis had rights to 1st car as he was 1st to place a full deposit, but gave those rights to me as my 46th bday present. Tks Ira!," Musk said on Twitter.

Musk has said that production should ramp up quickly with 100 Model 3s produced in August, followed by 1,500 produced in September and up to 20,000 produced per month starting this December.

These people: So, who exactly are the people approving the outrageous compensation packages for Apple (AAPL - Get Report) CEO Tim Cook and Netflix Inc.'s (NFLX - Get Report) top dog Reed Hastings? BoardEx, the relationship mapping service of TheStreet Inc., examined the directors who hold this power. The biggest takeaway: some of these people are on the boards for way too long.

Amazon Prime Day is here: Amazon's (AMZN - Get Report) Prime Day will kick off on July 10 at 9 p.m. ET and run through July 12 at 3 a.m. ET, with new deals being offered every five minutes. People who aren't Prime members already can sign up for a membership on or before July 11 to take part in the big sales event. TheStreet has full coverage here.

Amazon's inaugural Prime Day in 2015 was created to celebrate the company's 20th birthday and led to more new Prime subscribers than any other day in the company's history, Amazon said. Amazon did not divulge Prime membership signups for its second Prime Day in 2016, but did note that overall sales jumped 60% from 2015.

Not yet on this super IPO: The public listing of Saudi Aramco, possibly the largest IPO in history, looked very good on paper. After decades of reliance on a single, volatile commodity, Saudi Arabia would raise hundreds of billions of dollars to modernize its economy, while using the opportunity to improve its stature on the world stage. But, there are now a host of things that could derail this reported $2 trillion IPO, TheStreet reports.

Saudi Aramco CEO Amin Nasser reportedly said at the World Petroleum Congress in Istanbul on Monday the IPO could take place in the second half of 2018.

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