Especially if a company such as yours can help "saturate" a market (with no details, I can only speculate), you want to think carefully about whether you really should go after the entire market, and if your value would be less to each customer were you to have higher penetration.
To make up an example: there are companies selling templates for eBay sellers. The theory is the templates convert better than bland listings, and that therefore people using the templates have an advantage over those that don't. But if everybody uses them, the advantage to each may be greatly diminished.
It is also possible your solution doesn't make it any easier for companies to compete - in which case, why are they using it at all?
The answer is, to a first approximation: you don't. "Viral marketing" is a buzzword of the B2C sector. It exists in the BB sector, sure but it's never a dominant channel.
Do people regularly move between companies in the field?
Are there external companies/contractors hired by multiple companies in the field?