curl / Docs / Who and Why / The Name Curl

Who Owns the Name Curl?


The tool 'curl' was released on March 20 1998 for the first time. Before that it had been using other names, but as the tool matured the other names were not really suitable anymore. We were not aware of any name collisions when we picked this name.

A company named Curl Corporation registered their domain on November 19 1997.

Curl Corporation owns a US trademark (Serial Number 75487363) on the name "CURL", filed on May 18 1998.

Daniel Stenberg (head of the curl project) is living and working in Sweden, where there is no trademark ("varumärke" in swedish) or similar on the word curl.

Daniel Stenberg was contacted by a Curl Corporation representative for the first time on August 11th 2001 (possibly due to a slashdot article that appeared on August 6 about their CURL content language where lots of people mentioned the name collision).

Other software and computer related projects have also used and are using curl in their names. The curl project and the Curl Corporation are not the only ones.

Here follows an excerpt of the mail regarding the name issue that Daniel mailed mr Bob Batty at Curl Corporation on August 13th 2001, as a reply to his query about what we thought about the name problems.


First, I would like to say that I greatly appriciate your approach and I am indeed willing to participate in a dialogue to work things out. We too, of course, recognize the confusions our duplicate uses of the name 'curl' might cause. We have a section in our FAQ document for this reason that clearly states that "We are in no way associated with or their CURL programming language".

I am the original author, lead developer and maintainer of curl, but curl is truly the work of a large amount of people. We have more than 70 persons mentioned in the THANKS file for having done non-trivial contributions. This said, I try to make decisions in/for the project that I feel I have backing from the involved project members to do. I am discussing this subject with the rest right now.

We have been using the name "curl" since March 1998, we have both the tool curl and the curl library named libcurl (both being used by numerous programs and tools). We have a range of related sub projects named things like pycurl, tclcurl, rexxcurl and we have a module for PHP that is called just curl. Curl and libcurl are finding their way into more and more Linux distributions' main installations and recently, they have also been adopted in the Open Packages project which in practise eventually might make them pre-requisite for all freely available BSD operating systems as well.

I am willing to offer a distinct-looking "box" or similar, on the front page of the website at, that informs visitors about your project/product and a link to your site. To clearly show that we are not you. I would of course enjoy something similar from you.

So far, we have not seen a single user that seems to have mistaken our curl for yours. We will of course not hesitate to direct people your way, should we suspect that they are potential users/searchers of your CURL.

Do you have any other suggestions?

We have not received any further requests, questions, advice or suggestions from any person at Curl Corporation.

Curl Corporation used to recognize the name problem on their Linux FAQ page, but as of September 2002, they seem to have removed it. The exact wording they used was:

2. What's the difference between curl and Curl Corporation?

curl is a cool, very useful utility for transferring files that was created by Daniel Stenberg and can be found at Curl Corporation is the commercial producer of the Curl language, the Surge Runtime Environment, and the Surge Lab IDE.

That 'Linux FAQ' by was once available at this URL: (the links takes you to the version).