Prime Day deals Roku sale Juneteenth Super Mario Game & Watch Father's Day How to use IRS tools for child tax credit hammered by flurry of downgrades Inc. (Nasdaq: FATB) tumbled 5 5/16, or 26 percent, to 15 7/16 Friday after a trio of investment houses downgraded the online bookstore.

Banc of America Securities and Piper Jaffray cut the stock from a "strong buy" recommendation to a "buy" while Needham & Co. slashed it from a "strong buy" rating to a "hold."

Banc of America analyst Tom Courtney said the downgrade was the result of weaker-than-expected sales of its eMatter product, a system that allows people to securely publish and sell their writing online while earning royalties of at least 50 percent on each copy sold.

"While it is just three months into eMatter's launch, the associated costs have been above our previous assumptions and the ramp up in corresponding sales has been slower than expected," Courtney said in a research report. "The main challenge for eMatter, thus far, has been obtaining compelling content in a timely manner."

He also raised his fiscal 2000 loss estimate from $2 a share to $3.50 a share.

Last quarter, lost $9.1 million, or 80 cents a share, on sales of $8.2 million.

First Call consensus expects it to lose 85 cents a share in its fourth quarter and $2.64 a share in the fiscal year. shares moved up to a 52-week high of 42 1/4 in November after bottoming out at 11 5/8 in March.