After market close, shares had plummeted 35.4% to $32.11.
The data security software developer said it expects total revenue for its March-ended quarter between $31 million and $31.5 million compared to previous guidance of $36 million to $37 million.
Adjusted net losses between 40 cents and 44 cents a share were wider than a previously-announced net loss range of 33 cents to 37 cents a share.
Analysts surveyed by Thomson Reuters forecast a net loss of 35 cents a share and revenue of $36.69 million.
"Our first-quarter results were primarily impacted by extended sales cycles on deals over $100,000, which led to delays in receiving anticipated orders from customers, particularly in the U.S., which resulted in lower than expected revenue for products," said CEO, Shlomo Kramer in a statement.
The company is scheduled to report full financial results for the three months to March 31 after market close on May 1.
TheStreet Ratings team rates IMPERVA INC as a Sell with a ratings score of D+. TheStreet Ratings Team has this to say about their recommendation:
"We rate IMPERVA INC (IMPV) a SELL. This is driven by a number of negative factors, which we believe should have a greater impact than any strengths, and could make it more difficult for investors to achieve positive results compared to most of the stocks we cover. The company's weaknesses can be seen in multiple areas, such as its deteriorating net income, disappointing return on equity and feeble growth in its earnings per share."