Interactive Brokers Group Inc ( IBKR ) shares are trading higher in Monday's after-hours session after it was announced the company will join the S&P 500.

What Happened: After the market close on Monday, S&P Dow Jones Indices announced that automated global electronic broker Interactive Brokers ( IBKR ) will replace Walgreens Boots Alliance in the S&P 500, effective prior to the market open on Aug. 28.

The index shakeup comes as Sycamore Partners is set to acquire Walgreens Boots Alliance in a deal expected to be completed soon. Talen Energy will take Interactive Brokers’ spot in the S&P MidCap 400.

Shares of Robinhood Markets Inc ( HOOD ) and AppLovin Corp ( APP ) are moving lower in extended trading Monday as the companies had been considered strong candidates for potential S&P 500 inclusion. Robinhood was down 0.75% and AppLovin ( APP ) was down approximately 0.40% at last check, per Benzinga Pro data.

How To Buy IBKR Stock

By now you're likely curious about how to participate in the market for Interactive Brokers Group ( IBKR ) – be it to purchase shares, or even attempt to bet against the company.

Buying shares is typically done through a brokerage account. You can find a list of possible trading platforms here. Many will allow you to buy “fractional shares,” which allows you to own portions of stock without buying an entire share.

If you're looking to bet against a company, the process is more complex. You'll need access to an options trading platform, or a broker who will allow you to “go short” a share of stock by lending you the shares to sell. The process of shorting a stock can be found at this resource.

Otherwise, if your broker allows you to trade options, you can either buy a put option, or sell a call option at a strike price above where shares are currently trading – either way it allows you to profit off of the share price decline.

IBKR Price Action: Interactive Brokers ( IBKR ) shares were up 4.33% in after-hours Monday, trading at $65.49 at the time of publication, according to Benzinga Pro.

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