Word to refer to the person who creates something that gets reused or remixed?

I am looking for a noun to describe the role of "Person A" in the following scenario.

1. Person A makes a digital project (e.g. a video game, animation, video, etc).
2. Person B creates a digital project using Person A's project, either parts or the whole thing.

I am calling Person B's project a remix of Person A's project. Also, I am calling Person B a remixer.

What would you call Person A? Some of the terms I've used are but that I am not 100% happy with are:

• remixee. I like this one but its a bit obscure and easy to visually confuse with the term remixer.
• original creator. This is easy to understand but it's two words and it has the problem that it makes it seem as if the remixer is not original, which has a subtle but negative undertone.
• originator.

Other ideas?

In copyright law, party B's work is called "derivative". The previous work is called "preexisting", so he could be described as the "preexisting author".

progenitor

1. An originator of a line of descent; a precursor.
2. An originator; a founder: progenitors of the new music.

You might want to try out first party or principal.

Creator?

Source?

Author?

Interesting question :-)

These are reasonable multi-word stabs:

• "Author of the original work"
• "Original Author"
• "Principal Author"
• "Prima facie Author"

I like your idea "originator" but it lacks zing, and it lacks the implied Authorial ownership, and thus, if you really really want to drop it down to a single word, I can only suggest using a term which preserves the dignity of their essential ownership:

• "Author"
• "Creator"

Then, for the derivatives, call them "Mixologists", "Mashupologists" or something like that.