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What: Shares of Ariba (Nasdaq: ARBA) soared as much as 16% in early trading on heavy volume, after German software supplier SAP (NYSE: SAP) announced plans to acquire online HR specialist SuccessFactors (Nasdaq: SFSF) for $3.4 billion.

So what: Issues notwithstanding, Ariba could enjoy a similar takeout bid. The one-time dot-com darling continues to make a good living supplying online tools for sourcing supplies, technology, and the like. SAP and Oracle (Nasdaq: ORCL) are its top competitors.

Now what: What would its larger rivals pay? SAP is bagging SuccessFactors for about 7.6 times sales; Ariba trades for 6.3 times sales as of this writing. The delta could make for an interesting arbitrage opportunity -- but only if you believe an acquisition is inevitable. What's your take? Would you buy shares of Ariba at current prices? Please weigh in using the comments box below.

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.