Investors were talking about -- and, crucially, buying -- shares of Curaleaf (CURLF 2.39%) on the first day of the trading week. Monday saw the marijuana company's shares close more than 3% higher on news of inclusion in a prominent equity index. That rise was well higher than the 0.2% increase of the bellwether S&P 500 (^GSPC -0.38%) on the day.
Tapped for a top north-of-the-border index
Curaleaf was a topic of discussion and target for investment because it's ascending to the S&P/TSX Composite Index, considered to be the leading index for Canadian stocks (in addition to trading over the counter in the U.S., it is listed on the Toronto Stock Exchange). The move takes effect before market open on Monday, Sept. 22.

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The index's owner, S&P Global, makes quarterly adjustments to its indexes, and Curaleaf was included in the latest one. It was one of five companies selected for inclusion, and the only one from the broader healthcare sector.
In its own press release on the move, Curaleaf didn't hesitate to point out that this will make the company the first U.S.-headquartered pot company to be included on the S&P/TSX Composite.
A higher profile
Not only that; Curaleaf quoted CEO Boris Jordan as saying:
Being recognized among some of the most influential stocks in North America, and as the only U.S.-based cannabis operator currently in this index, validates our sector's growing legitimacy and long-term potential. Our inclusion reflects an expanded presence in public markets and broadens our access to institutional investment and index-linked vehicles as we navigate the industry's ongoing development, alongside potential regulatory catalysts.