A Fidelity fund has slashed its estimate of Twitter's value amid ongoing chaos at the company, implying the social media platform may be worth only a third of its value compared to when Elon Musk acquired it in October.

According to a monthly disclosure, Fidelity's Blue Chip Growth Fund reported that its stake in Twitter was worth $6.55 million at the end of April.

That's down from the $19.66 million the Fidelity fund said its stake was worth in October as Musk was finalizing the acquisition. The revision implies Twitter may be worth only $15 billion overall, as opposed to Musk's $44 billion purchase price.

Fidelity did not provide a reason for the markdown in its disclosure nor an explanation of how it arrived at its valuation, but the adjustment coincides with widespread public blowback to Musk's erratic decision-making.

Under Musk's watch, Twitter has laid off much of its staff, lost many of its advertisers and embarked on a troubled rollout of a paid subscription service and the end of traditional user verification that has led in some cases to impersonations of brands and high-profile accounts.

Fidelity has repeatedly marked down Twitter's value. Its stake was worth $8.63 million in November and then $7.8 million in January, Reuters has previously reported. This week's figures were first reported by Bloomberg.

The Fidelity report is dated April 28, so it does not reflect recent changes in Twitter's leadership. Earlier this month, Musk announced that former NBCUniversal advertising exec Linda Yaccarino would be taking over as Twitter CEO, though Musk has said he would continue to play significant roles as executive chairman and chief technology officer.

-- CNN's Matt Egan contributed reporting.