Upgrade lifts DigitalThink shares

DigitalThink shares rallied up 8 7/8, or 26 percent, to 43 1/2 Tuesday after Goldman Sachs upgraded the stock from a "market perform" rating to a "trading buy."

DigitalThink (Nasdaq: DTHK) provides online learning courses and services.

In its latest quarter, DigitalThink posted a loss of $6.1 million, or 18 cents a share, on sales of $6.3 million.

First Call Corp. consensus expects the San Francisco firm to lose 18 cents a share in its third quarter and 69 cents a share in the fiscal year.

Its shares rallied up to a 52-week high of 62 in July after falling to a low of 15 in April.

Six of the seven analysts tracking the stock rate it either a "buy" or "strong buy."