Regulators are attempting to save Twitter-hungry investors from themselves.

The Financial Industry Regulatory Authority changed the ticker symbol of Tweeter Home Entertainment Group, a long-closed electronics retailer, on Tuesday after its stock soared last week when investors apparently mistook it for Twitter.

Tweeter previously traded under the symbol "TWTRQ," but will now be listed as THEGQ (THEGQ). Q is typically added to the ticker symbols of bankrupt companies that still have shares trading.

FINRA said it changed the symbol for "the avoidance of further confusion" following "a widespread misunderstanding related to the possible initial public offering of an unrelated security."

Twitter plans to trade under the symbol TWTR when it goes public. The company filed papers last week detailing its plans for a $1 billion initial public offering.

A day later, shares of Tweeter Home Entertainment Group soared as high as 15 cents, a gain of about 1400%. Shares finished the day at 5 cents, up nearly 700%.

The stock had a similar spike back on Sept 17, a few days after Twitter's initial filing signaling its plans to go public.

People who hold shares in defunct companies like Tweeter can still trade them. But the shares trade on over-the-counter markets rather than on any of the major exchanges.