Incorrectly detected 'proprietary-license'

[chinyeungli]

Description

The following license text is incorrectly detected as "proprietary-license"

Copyright 2025 Sinusoidal Systems AB

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
of the Software, and to permit persons to whom the Software is furnished to do
so, subject to the following conditions:

1. The above copyright notice and this permission notice shall be included in
   all copies or substantial portions of the Software.

2. Redistributions of the Software in source or binary form must include an
   attribution notice stating that the Software was originally developed by
   Sinusoidal Systems AB, and may not in any way suggest that Sinusoidal Systems AB
   endorses or is affiliated with the redistribution or derivative work without
   prior written permission.

3. Neither the name, trademarks, nor service marks of Sinusoidal Systems AB may be
   used to endorse or promote products derived from this Software without specific
   prior written permission.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

(https://docs.rs/crate/sinusoidal/0.4.0/source/LICENSE)

Scan result:

    {
      "path": "LICENSE",
      "type": "file",
      "detected_license_expression": "proprietary-license",
      "detected_license_expression_spdx": "LicenseRef-scancode-proprietary-license",
      "license_detections": [
        {
          "license_expression": "proprietary-license",
          "license_expression_spdx": "LicenseRef-scancode-proprietary-license",
          "matches": [
            {
              "license_expression": "proprietary-license",
              "license_expression_spdx": "LicenseRef-scancode-proprietary-license",
              "from_file": "LICENSE",
              "start_line": 3,
              "end_line": 29,
              "matcher": "3-seq",
              "score": 93.79,
              "matched_length": 166,
              "match_coverage": 93.79,
              "rule_relevance": 100,
              "rule_identifier": "proprietary-license_390.RULE",
              "rule_url": "https://github.com/nexB/scancode-toolkit/tree/develop/src/licensedcode/data/rules/proprietary-license_390.RULE"
            }
          ],
          "identifier": "proprietary_license-5b842126-ef54-c1c5-7e3a-b98a6dc8ef9a"
        }
      ],
      "license_clues": [],
      "percentage_of_license_text": 67.21,
      "scan_errors": []
    }

[omkar433434343]

Hi! I'd like to work on fixing this issue. Could I please be assigned to it?

I've analyzed the license text and confirmed it's clearly an MIT License variant with attribution clauses, not a proprietary license. The text includes standard MIT permission grants and disclaimer.

Could someone from the team provide guidance on the best approach to fix this? Should I:

1. Add a new MIT-variant rule?
2. Modify the existing proprietary-license_390.RULE to exclude MIT-based patterns?
3. Something else?

thanks a lot

[ionfwsrijan]

@chinyeungli
Hi there,

I’m Srijan Jaiswal, and I’m eager to contribute to this project as part of my open-source contribution. I have reviewed this issue and feel confident that I can provide a solution since I have experience working with similar technologies in my past projects. Could you please assign this issue to me? I’d love to work on it and contribute to the project.

Best regards,
Srijan Jaiswal

[AbhayXplorer]

Hi there,

I’m interested in working on this issue. I’ve gone through the issue description and I understand the problem. If this issue is not already assigned, could you please assign it to me? I’d love to contribute and submit a PR.

Thanks!

[dikshaa2909]

Hi, thanks for reporting this @chinyeungli

I reproduced the issue locally and confirmed that this license text is an MIT-style permissive license with attribution and non-endorsement clauses, not a proprietary license.

My plan is to address this by adding a new MIT-variant license rule (rather than modifying the existing proprietary rule), so the matcher can correctly classify this text. I’ll also add a regression test to ensure this behavior doesn’t regress in the future.

I’ll go ahead and work on a PR with this approach unless there are any objections or a preferred direction.