Take a look at the companies making headlines in midday trading. Fortinet – The cybersecurity stock was the biggest gainer on the S&P 500 on Wednesday, soaring 26% after Fortinet reported a strong second-quarter report and upbeat current-quarter guidance. The cybersecurity company reported adjusted quarterly earnings of 57 cents per share on revenue of $1.43 billion. Analysts polled by London Stock Exchange Group (LSEG) expected earnings of 41 cents per share on revenue of $1.4 billion. Shopify – The Canadian e-commerce company’s second-quarter results beat expectations, sending the company’s shares up more than 22%. Shopify said it expects third-quarter revenue to grow about 20% compared with the same period last year. Analysts had expected sales to rise 20.9% annually, according to FactSet. Lyft — Shares of Lyft fell more than 12% after the ride-hailing company issued weaker-than-expected third-quarter guidance. Lyft expects adjusted earnings before interest, taxes, depreciation and amortization to be in a range of $90 million to $95 million. Analysts expected the figure to be $103.4 million, according to FactSet. Airbnb — Shares plunged more than 13% after the company issued weaker-than-expected third-quarter revenue guidance. Airbnb expects revenue to be between $3.67 billion and $3.73 billion, while analysts polled by FactSet expected revenue of $3.84 billion. Super Micro Computer – The server company's stock price fell 16% after the server company reported fourth-quarter earnings that were lower than expected and gross profit margins fell. This overshadowed strong guidance due to continued artificial intelligence demand. Super Micro Computer also announced a 10-for-1 stock split. Lumen Technologies – Shares of Lumen Technologies soared 40% after the cloud-based network data company reported second-quarter revenue that beat Wall Street expectations. Lumen reported revenue of $3.27 billion, while analysts polled by LSEG expected revenue of $3.25 billion. Goldman Sachs also raised its rating on the stock to neutral from sell. Lumen has been hot this week as it announced $5 billion in new business, driven by demand for artificial intelligence. Upstart Holdings — Shares of Upstart Holdings soared 49% after the company reported better-than-expected quarterly results. Upstart reported an adjusted loss of 17 cents per share on revenue of $128 million. Analysts expected a loss of 39 cents per share on revenue of $125 million, according to LSEG. Novo Nordisk – Shares of Novo Nordisk fell 8% after drugmaker Wegovy reported disappointing second-quarter results and lowered its full-year operating profit forecast. While the stock has gained more than 25% so far this year on optimism about its weight-loss drug, the latest report has raised concerns that the company is facing pressure from Eli Lilly's Zepbound and Mounjaro. VF Corporation – Shares of VF Corporation rose about 12% after the company reported better-than-expected first-quarter earnings results. VF Corp reported an adjusted loss of 33 cents per share on revenue of $1.91 billion. That was better than the consensus estimate of a loss of 37 cents a share on revenue of $1.85 billion, according to FactSet. Sunrun – Shares of Sunrun soared more than 12% after CEO Mary Powell revealed the company was in talks with many of SunPower's former resellers and even invited some to become partners. This comes after SunPower filed for Chapter 11 bankruptcy protection on Monday. Global Payments – Shares of Global Payments rose about 8% after the company beat Wall Street expectations for second-quarter profit. Global Payments reported adjusted earnings of $2.93 per share. Analysts polled by FactSet expected earnings of $2.91 per share. Amgen – Shares of Amgen fell more than 5% after the biotech company missed Wall Street’s profit expectations. Amgen reported adjusted earnings of $4.97 per share, below the $4.98 per share expected by analysts polled by FactSet. The company also narrowed its full-year profit forecast. Rivian Automotive—The company’s second-quarter net loss widened to $1.46 billion from $1.2 billion in the same period last year, and the company’s electric vehicle shares fell more than 2%. The company beat expectations on some metrics and reported an adjusted loss of $1.13 per share. Analysts polled by LSEG expected a loss of $1.21 per share. Advanced Micro Devices – Piper Sandler reiterated that it is a top choice company and expects its market share in the traditional server market to grow “significantly”, sending its shares up nearly 2%. Analyst Harsh Kumar expects upside potential of over 30%. Reddit – Shares of Reddit fell 5.7% despite the social news company reporting second-quarter results that beat revenue and profit estimates. Reddit also issued a third-quarter outlook, saying it now expects sales to be between $290 million and $310 million, while analysts expected $278.7 million. —CNBC's Sarah Min, Jesse Pound, Samantha Subin, Pia Singh and Michelle Fox contribute.