• The Nasdaq closes at a fresh record to kick off the second half.
• Paramount Global is looking for a streaming partner.
• The Boston Celtics is planning to be sold.

Here are five key things investors need to know to start the trading day:

1. Starting off strong

All three major indexes kicked off the second half on a positive note, posting gains for Monday's trading session. The tech-heavy Nasdaq Composite closed the session at a fresh record, gaining 0.83% to end at a high of 17,879.30. The S&P 500 and the Dow Jones Industrial Average also closed higher, with the broad market index gaining 0.27% and the Dow gaining 0.13%. The tech sector also finished with gains to start the second half, moving 1.3% higher. Tech stocks Microsoft, Apple and artificial intelligence darling Nvidia advanced 2.2%, 2.9% and 0.6%, respectively. Follow live market updates.

2. New deal?

Paramount Global is making moves on merger talks. According to people familiar with the matter, the company's leadership is actively meeting with executives at other media and tech companies to explore merging Paramount+ with another streaming entity and having the platform become co-owned. People familiar with the matter also said that Warner Bros. Discovery has expressed interest in a deal being reached, as a Max and Paramount+ combo could increase their competitiveness with the array of platforms from Disney – namely, Disney+, Hulu and ESPN – other platforms like Netflix. This comes after Warner Bros. Discovery previously held preliminary merger talks earlier this year. A streaming deal, if reached, could lead to other streaming partnerships across the media industry.

3. Boston Sale-tics

The Boston Celtics may soon get sold. The team's ownership group has announced that it plans to sell it, with the controlling family of the group saying it intends to sell all of its shares in the team "for estate and family planning consideration." The sale of a majority stake is expected to be completed by the end of this year or early next year, and the remainder of the sale would close in 2028, according to a statement. The sale combined with the cost of sports media rights could lead to a valuation close to a record $4 billion or more, which is the amount the NBA's Phoenix Suns reached in 2023.

4. Uncompensated

It looks like top executives at Salesforce may not get a compensation plan. Investors have voted against the plan after shareholder advisory groups expressed concerns about equity awards that CEO Marc Benioff had been granted. A regulatory filing on Monday showed that 339.3 million votes were made in favor of approving the plan, while 404.8 million votes were made against. This is despite the fact that the board had urged shareholders to support the resolution. However, two shareholder advisory firms – Glass Lewis and Institutional Shareholder Services – had advocated for striking down the resolution. Earlier this year, the board's compensation committee gave Benioff a second long-term equity award worth $20 million for the company's strong performance, among others.

5. Immunity

The Supreme Court has sided with Donald Trump. In a 6-3 ruling, the court decided on Monday that the former president has "presumptive immunity" for official acts he performed as president. This throws a wrench into the election interference case brought forth by special counsel Jack Smith. Though, the former president is not immune for "unofficial acts," the court ruled, with the majority further specifying that "not everything the President does is official." As a result, the case will be sent back to U.S. District Judge Tanya Chutkan. Now, the chances that the criminal case against Trump will head to trial before the Nov. 5 election have been squashed.

— CNBC's Brian Evans, Samantha Subin, Alex Sherman, Lillian Rizzo, Jordan Novet and Kevin Breuninger contributed to this report.

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