This is the type of thing that makes the creative side of me come out. Do you know the company with the patent?? or pending patent??
First of all, it's illegal to say 'Patent Pending' if there isn't an actual application. And... I think I read somewhere that you can only use that for a specified period of time, because the Patent will either be issues... or it's dead.
Now, understand this. I am pretty sure that any lawyer will tell you this... it's just that I am going to lay it out from the 'business' side.
The reason I asked if you knew the company is because it's good to know who you're going to do battle with. If they have deep pockets, you are not going to win in the long run, unless you're prepared to spend big too.
What you need to remember about Patents is that it's up to the PATENT OWNER to defend the Patent. People get this gitty idea that as soon as they have a patent, the patent fairy is going to look after everyone who attempts to even LOOK at you funny. The SOLE RESPONSIBILITY is on the patent owner (That's why I wouldn't recommend it for small business owners... you don't have the money to defend it).
Therefore, assume the worse. You go ahead. IF they find out... they send you a 'Cease & Disist' letter, basically telling you to stop.
If you continue, they can sue and get the profits from you. That's where it get's expensive. But also understand that THEY have to have the money to START the suite. So they have to be sure...and know that there is money in the product to do that.
In short... I have taken chances. In one case, the company that owned the patent went out of business. The product wasn't one of those million dollar items... but it made money. So you have to decided.
Just remember... first they have to find you... and depending on how big they are and how much money they have... that may never happen. Then they have to approach you. Typically the first contact is a letter. Then you have to decide.
Good luck. This is NOT intended to be legal advice.