Fidelity is one of the few companies who is publicly estimating the value of Twitter.
Fidelity is an owner of Twitter equity (one of the groups who kept their shares after Elon Musk bought the rest of the company). Since Fidelity is a financial firm, they try to estimate the value of their holdings.
By the numbers: Fidelity believes that X is worth 71.5% less than at the time of purchase, according to a new disclosure that runs through the end of November 2023 (Fidelity revalues private shares on a one-month lag).