SAP co-ceo Bill McDermott AP SAP has changed its software license so it can slap customers with massive fees, a consultant is warning.

SAP shocked three of the consultant's clients with bills ranging from $3 million to $6 million for violating the company's "indirect access" licensing terms -- and that's on top of the license fees they paid to SAP to buy its software, says Dave Blake, CEO of UpperEdge in Boston. UpperEdge helps companies negotiate software licenses with big companies like SAP, Oracle, Microsoft, etc.

Blake is alarmed at this new tactic by SAP, he told Business Insider.

Essentially, if you put information into a SAP application -- like your company's sales data -- and you would like to send that same data to another application, SAP wants to charge you for that. The software company has added a new thing to its license agreement that forbids companies from taking data out of SAP systems to use with a non-SAP application.

"Imagine a scenario where you buy a new camera that takes great digital pictures. You paid for the camera and the software to manage the photos. Now the camera manufacturer wants to charge you every time you want to send a photo to somebody or paste it onto a web-page etc. SAP is trying to do the same thing, only with the your data," warns Blake.

Plus, SAP has gotten "more aggressive" in going after customers if they violate this wild licensing term.

SAP admits that they added the new licensing term but says customers shouldn't be surprised by it.

"We have introduced new global terms and conditions with clear language that also respects SAP’s intellectual property. We want the conditions to be as simple to understand as possible for our customers and have adopted language that is more specific," a spokesperson told us. The spokesperson also took a jab at Blake claiming he was "misinformed or operating on old information."

Blake says, surprised or not, if an enterprise gets a big bill based on "indirect use" they should fight it. Customers should also make sure that SAP fully defines what it means by "indirect use" -- including examples of a violation -- before they sign a new contract.

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