photo agency and commercial rights
I'm an amateur photographer and I received a proposal by an agent of a german press and photo agency: they are interested in taking some my photos into the agency. I get a draft supplier agreement to check the conditions.
A part of the contract: " The Agent acknowledges that the Material remains the property of the Supplier and that copyright remains with the Supplier or its suppliers. The Agent will make Sales to editorial clients in the news media (including, but not limited to, magazines, newspapers, TV news and online news channels). The agreement does not include commercial rights. "
I am totally new to this business, is this a normal clause of a contract between a photographer and an agency?
what does mean 'The agreement does not include commercial rights'?
The contract involves that I do transfer the commercial rights of my photos to the agency? can you explain me this concept?