How close to a trademark can I get before I'm at risk of getting sued?

Background So, you may have heard of the "Net Promoter Score" which is trademarked term and is a metric for customer satisfaction and loyalty. Basically, there is a formula for calculating the likelihood of your company being recommended by your customers... which is an indicator of growth. The company who came up with that is here: http://www.netpromoter.com/ and they have their own data collection software to help you calculate that score.

Well, I built an application that basically makes it really easy to collect this information from your clients and then analyze the data in a useful way... otherwise you'd have to go fashion your own forms using form data tools like Survey Monkey, or something like that.

Other products use this system and have similar names I've looked around, and there are other companies doing basically the same thing, who also make reference to it by name, like the Net Promoter System (NPS) and Question Pro's Net Promoter Score survey system So, can I? When building this app, I bought the domain name NPSFeedback.com and planned on calling it that. Is using the name "NPSFeedback " violating their trademark protection? Also, is it allowed to even make an app to help collect NPS at all?

How close to a trademark can I get before I'm at risk of getting sued? The chance of getting sued is entirely up to them. On one extreme you could be sued for something absolutely frivolous even if they have no chance of winning, and on the other extreme the other party could choose not to file a lawsuit even if they have grounds to win the case. At the end of the day, choosing to file a lawsuit is based more on emotions than legal justification.

Is using the name "NPSFeedback" violating their trademark protection? I suspect so, but I don't feel very qualified to answer this. Ask a trademark lawyer.

Also, is it allowed to even make an app to help collect NPS at all? You can certainly create an app that collects feedback, unless they somehow had a patent on that (which is hard to believe). Their trademark only protects the name "Net Promoter Score" and its likeness (e.g. abbreviations). If you want it to integrate with their system, you'll need to contact them.

Lets take a more common example that everyone knows. The company United Parcel Service, does not explicitly own a trademark for just UPS. But imagine if you created a website UPSfeedback.com, and the site was marketed as a feedback site about UPS. Would you be sued for trademark infringement? In a second, there is no doubt. Would they have a case? Also yes.

You need a new name for your website and your business.

I wouldn't build NSP in to your product name like NSPfeedback.com.

Do something else for your core business name so you don't risk it. In my 'opinion' it's a gray area that a cease and desist from them at any point in the growth of your business will force you to change your name or go to war with them.

Do a different name.

You can probably still market it as:
"compared to NSP", "Similar to Net Promoter Score calculations..." or something like that if there is a benefit of letting people know that.