Stocks making the biggest moves midday: Roblox, Penn Entertainment, Upstart and more

cnbc.com:

Check out the companies making headlines in midday trading.

Roblox — Shares tanked 20% after the online gaming platform fell short of second-quarter estimates. Roblox reported a loss of 46 cents per share, versus the 45 cent loss expected by analysts polled by Refinitiv. Revenue came in at $781 million, shy of the $785 million anticipated. The revenue figure is referred to as bookings by Roblox.

Penn Entertainment, DraftKings — Shares of sports betting company Penn Entertainment surged 7% a day after the firm said it is partnering with Disney-owned ESPN to rebrand and relaunch its sportsbook as ESPN Bet in a 10-year deal. It's the first time ESPN's brand will be on a sports betting platform. Penn rival DraftKings saw shares dropping 9% following the news.

Upstart — Shares plunged more than 32% on disappointing guidance. Upstart, a consumer lending platform, said it expects third-quarter adjusted EBITDA and revenue to come in around $5 million and $140 million, respectively. Analysts estimated $155 million in revenue and $9.6 million in adjusted EBITDA, per StreetAccount. Despite the stock move, the company reported second-quarter results that topped estimates, including a surprise adjusted profit of 6 cents a share.

Lyft — The ride-sharing company's shares tumbled about 8% following its second-quarter earnings announcement after the bell Tuesday. Lyft posted revenue of $1.02 billion, which came in line with analysts' estimates, according to Refinitiv. The company's adjusted earnings came in at 16 cents per share, beating estimates of a loss of 1 cent per share. However, the company's revenue per active user declined following the company's efforts to reduce ride fares to compete with Uber.

Rivian — Shares of the