Why Nano Nuclear Energy Stock Was Sliding This Week

Key Points

• Investors didn't seem impressed that the nuclear power specialist ascended to three stock indexes.

• The trio is managed by the same company behind the S&P 500 index.

• 10 stocks we like better than Nano Nuclear Energy ›

According to data compiled by S&P Global Market Intelligence, Nano Nuclear Energy's (NASDAQ: NNE) share price had eroded by almost 11% week to date as of Thursday night. This, despite the fact that the company was included on several stock indexes managed by a well-known indexer.

Come and join

Before market open that day, Nano announced that its stock is now a component of not one, not two, but three equity indexes managed by S&P Dow Jones Indices. The trio is the S&P Global Broad Market index (BMI), the S&P Total Market index (TMI), and the SPX Completion index.

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These, however, are not as closely tracked and have less prominence than other equity gauges in the S&P family (most notably the S&P 500 index).

At least Nano has plenty of company. In terms of composition, the BMI is certainly sprawling. As of the end of August, it has 14,782 component stocks, which are collectively headquartered in 48 countries around the globe.

The other indexes are notably smaller, at 3,360 for S&P Completion and 3,865 for TMI. The two are related -- S&P Completion has the same composition as TMI, except with the stocks also on the S&P 500 index stripped out.

The good old index effect

Nano's ascensions definitely represent an advancement for the next-generation nuclear company. However, many investors might be thinking they aren't enough of an advancement, since in prestige and visibility terms, the trio is under the level of closely monitored mainstays, again like the S&P 500 index.

Nevertheless, if it hasn't already been discovered and researched simply by its presence in the currently hot nuclear sector, Nano will soon go under the microscope by a host of index funds. After all, such vehicles are constantly on the hunt for good investments among a relatively limited pool of stocks.

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Eric Volkman has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.