Yahoo chief executive Marissa Mayer has been changing a lot of things at the technology firm, and a report from Business Insider shares that she may be making yet one more change to the company culture.

According to a memo obtained by the news site, Mayer has said that she’ll give every Yahoo employee a new smartphone — as long as it’s an Apple iPhone 5, Samsung Galaxy S III, HTC One X, HTC EVO 4G LTE or a Nokia Lumia 920.

Conspicuously absent from the list, of course, is the phone that’s long been the stalwart of the enterprise market — the BlackBerry. Business Insider said that it received the memo from one Yahoo employee and verified it with another.

Yahoo is moving off of RIM’s platform “as our corporate phones,” the memo said.

Mayer’s reasoning?

According to the reported memo: “A few weeks ago, we said that we would look into smartphone penetration rates globally and take those rates into account when deciding on corporate phones. Ideally, we'd like our employees to have devices similar to our users, so we can think and work as the majority of our users do.”

RIM’s stock fell over 4 percent in Monday trading as tech watchers cited Mayer’s decision as another piece of evidence that the Canadian smartphone maker is losing ground in the consumer and enterprise market. On Tuesday, RIM extended losses it suffered after the announcement, and opened at $7.17 per share. In mid-morning trading, the stock was trading at $7.23.

The company is expected to roll out smartphones running its new BlackBerry 10 platform early next year — a second delay the company announced in late June at the same time it said it would gut 5,000 jobs from its workforce.

At least one analyst predicted at the time that RIM would not survive to see the launch of its new platform, particularly with compelling products in the pipeline from Apple, as well as from manufacturers making Android phones and Windows phones.

Apple, particularly, has taken previously uncharacteristic aim at the enterprise market, touting the business-friendly features of the iPhone such as its extensive App Store and the ability to store word processing and other documents with its iCloud service.

RIM also faces serious competition for the enterprise market from Microsoft, which will aggressively market Office integration in its new Windows phones to businesses.

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