Public copyright license readability metrics

Promised boring topic blog post in form of README snapshot.

The README with tables removed has a Flesch Readability Ease score of 48.5, slightly worse than the average license text. I did not try to write intelligibly, though I should. The topic may have subconsciously restrained parenthetical discursiveness.


Automated readability metrics for public copyright licenses. Give style a list of plain license texts, generate HTML table containing metrics.

In Debian, style is available in the diction package.

License texts are referenced from the SPDX licenses list. Other license curiosities are included in licenses-other.

sh license-readability-html-table.sh licenses-spdx/*.txt licenses-other/*.txt

Background

Part of one of the goals of the Creative Commons (CC) licenses version 4.0 effort is to make the licenses "readily understood". One way to test that is with automated readability metrics, on which CC licenses version 3.0 score poorly (previous versions scored much better). I checked an early version 4.0 draft, and scored much better, more or less back to version 2.5 scores, quite an accomplishment given it is a more sophisticated license in many ways. I did not check again until the near-final 4th draft was published. Its score is not as good as early drafts, probably to be expected as details were settled, but still a big improvement over 3.0. I intended to blog the early 4.0 draft improvement at that time but didn’t get around to it.

In the meantime I’d peeked at the readability metrics for various free/open source software licenses, in part to see if copyleft-next scored better than comparable licenses (probably, though comparability is problematic). With the CC 4.0 licenses nearly final, I started a blog post about readability of various licenses, and ended up with this README and associated files.

See Caveats and Output below for readability metrics for about 228 licenses. There probably will not be any big surprises awaiting anyone familiar with the usual relatively popular licenses. A small selection of licenses not in the SPDX licenses list (including CC 4.0 drafts and copyleft-next versions) are at the end.

Next

Drafters understandably try hardest to "get the legal details right". But if "licenses are the constitutions of software communities"12, even a little bit (I think a casual reading of that quote makes licenses far more central than they are, or implies impoverished communities, but will take its repetition as an indicator of licenses’ social importance), perhaps yet more effort ought be put into making licenses more understandable.

  • There is probably a large literature on readability and understandability of contracts, legislation, regulation, and other legal texts, which ought be digested for lessons for the public copyright licensing community. Apparently many jurisdictions have "plain language" requirements for contracts. Some U.S. states require insurance forms to have a minimum Flesch Reading Ease score. Is this an indicator that readability metrics are useless, or should free/libre/open/software/knowledge communities be embarrassed that they have failed to self-regulate to this level?
  • Cloze testing and subjective evaluation (both requiring humans) and natural language processing/machine learning based metrics are suggested by a readability tools site in addition to simple automated readability metrics. The site, by Michael Curtotti, is presumably discussed in his forthcoming paper The Right to Access Implies a Right to Know: An Open Online Research Platform for Assessing the Readability of Law. Could some of these tools be useful for evaluating licenses? Barriers would include lack of interest needed to pay for human testing, and a relatively small corpus of license texts. Hopefully the source code for this platform will be made available.
  • Attempts to increase readability and understandability outside of changing the words in a license text could be evaluated, including summaries, FAQs, choosers, and typography and other design elements around web publication of the license text itself.
  • There are many additional obscure licenses intended for "content", "data", "government", and "hardware designs" not included in the SPDX license list that could be analyzed.
  • Non-English license texts could be analyzed with language-appropriate metrics. In addition to the few CECILL licenses included in the SPDX licenses list, targets could include the many official language versions of EUPL versions, unofficial translations of GPL versions, License Art Libre, various public sector-focused licenses, and hundreds of CC license "jurisdiction ports".
  • To what extent is understanding of licenses social, gained via hearsay, not based on reading license texts at all? If social learning currently predominates, does this indicate that license readability and understandability are unimportant? Or that their lack constitutes an obscurantist barrier to participation by people not socially connected to existing communities, and increase other risks, such as non-compliance through ignorance, and being ignored by policymakers?
  • Would it be valuable to use readability metrics to test other texts important to free/libre/open communities, e.g., documentation, codes of conduct, contributor agreements?

Caveats

General, with respect to the metrics:

  • Metric explanations are available in the style man page. All are problematic.
  • Lower numbers indicate better readability for all metrics except Flesch.
  • None of the metrics incorporate text length, so correlations with character count ought indicate that longer texts tend to use more or less readable language. But 3 of the metrics positively correlate readability with longer texts, and 4 negatively, which might indicate no overall correlation (taking the numbers at face value, with no further validation).
  • Not sure why Coleman-Liau’s correlations with other metrics are much weaker than among others; at a glance the formula is measuring the same types of things.
  • Arbitrarily choosing to focus on Flesch, as it seems widely used, and its more is better makes for an easier combination with text length, "Chars/(Flesch>=1)", to indicate how painful reading an entire license might be.
  • Flesch can be negative, so a minimum value of 1 is used for the pain calculation. This is arbitrary too.

The following tables are calculated in scratch.ods.

Readability metric correlations: nothing really surprising, no gross errors?
Kincaid ARI Coleman-Liau Fog Lix SMOG Flesch Chars/(Flesch>=1)
Characters 0.12 -0.10 -0.27 0.13 -0.15 0.25 -0.25 0.96
Kincaid 0.89 0.04 0.99 0.81 0.90 -0.91 0.32
ARI 0.30 0.89 0.97 0.70 -0.67 0.10
Coleman-Liau 0.07 0.41 0.11 -0.09 -0.20
Fog 0.82 0.93 -0.90 0.33
Lix 0.63 -0.59 0.04
SMOG -0.95 0.43
Flesch -0.43
Aggregate metrics: compare your favorite license to the masses and outliers.
Characters Kincaid ARI Coleman-Liau Fog Lix SMOG Flesch Chars/(Flesch>=1)
average 8318.7 12.8 16.0 14.5 16.1 59.1 13.4 50.7 177
median 7321.5 12.6 15.4 14.4 15.9 57.9 13.2 50.4 160
stdev 6864.8 2.9 3.5 1.4 3.1 7.4 1.8 11.1 152
min 209 4.5 8.2 10.3 7.0 42.5 7.6 -25.8 2
max 36285 37.0 45.7 18.0 40.3 116.8 24.9 83.3 806

With respect to particular licenses:

  • The CECILL licenses, except 1.1, are in French. These readability metrics may not be tuned for French, though the results do not look weird.
  • The CC by-nc-sa-4.0-drafts are drafts. Every other license analyzed is "released".
  • GPL-[version]-with-[exception name]-exception are not complete licenses, should be appended to the relevant GPL-[version]. However, standalone (as provided by the SPDX licenses list) provides an idea of how readable each exception is.
  • LGPL-3.0[+] incorporates GPL-3.0 by reference, so it is not directly comparable to GPL-with-exceptions above, nor with other licenses.
  • Some licenses (most notably [A]GPL and FDL) have a preamble or addendum which explain the license’s purpose and how to use the license. This makes such a license longer, but arguably increases understandability in a way not captured by an automated readability metric.
  • The only license with a negative Flesch score is the Historic Permission Notice and Disclaimer (HPND), which is deprecated. It deserves the score, basically being a template with many optional and fill-in parts.
  • The longest and also most "painful" to read license, the Adaptive Public License (APL), is also basically a template with options and fill-in parts.
  • The shortest and also least "painful" to read license, the Fair License might require too much imagination about what "usage" means to actually be easily understandable.

Output

SHA1 License Characters Kincaid ARI Coleman-Liau Fog Lix SMOG Flesch Chars/(Flesch>=1)
f53aa44a98a67f79d79bb061a39ac0694c017d88 AAL 2347 14.7 20.8 16.1 17.9 69.6 13.7 49.4 47
b26853ef3e258172c7bc9e7a69e9582d651c0269 AFL-1.1 3827 11.1 15.9 15.3 15.1 59.6 12.8 59.7 64
54f83bc9e70424af32e5a133c47e76698086369c AFL-1.2 4059 13.7 15.8 15.2 18.3 58.8 15.4 41.1 98
735e1f8b4613292d7d80e51e5a586e34ac852a74 AFL-2.0 7105 12.8 14.4 14.7 17.0 56.5 14.6 44.1 161
fedb7d79211a6e58a65b46985f47fa834b00ee6f AFL-2.1 7103 12.8 14.4 14.8 17.0 56.4 14.6 44.0 161
5b400f7a1518b5e43a913085fa338e3df1e9e241 AFL-3.0 8314 13.8 15.6 14.4 17.8 58.2 15.0 42.2 197
ecf6b4a3803b9706a0c38d30b0d07b0c624001ed AGPL-1.0 12578 19.0 23.4 12.5 21.9 71.9 14.8 38.0 331
c34c24e89e6c26506a4aa9535425afe6af4ab700 AGPL-3.0 27208 14.4 16.8 13.4 17.5 59.1 14.2 44.8 607
2b6ca3805481833fddead9c45f92fe4c81d4017d Aladdin 9270 13.6 16.9 13.2 17.0 60.1 13.5 51.6 179
295765ae399d1a9ced2bc4e1fb096e83e529cbfa ANTLR-PD 792 10.3 11.4 12.3 13.8 43.6 12.3 58.4 13
acc3577130a1e528970142d1e5180f554b7fdad9 Apache-1.0 2021 10.7 15.8 16.2 13.9 55.5 12.0 60.0 33
81d8a4169126e0af11b4d51449b6c420880c6d40 Apache-1.1 2017 11.0 16.5 17.9 14.0 60.0 12.3 55.7 36
8ffe2c5c25b85e52f42fcde68c2cf6a88b7abd69 Apache-2.0 8310 16.8 19.8 15.1 20.7 64.6 16.6 33.6 247
4f97e77af1aac9f8ef6500cd2a08915741c37f2c APL-1.0 36285 14.2 17.7 14.8 18.1 62.4 14.9 45.0 806
158031d76c5611507e81870b0a649461eb74be7f APSL-1.0 15302 12.5 15.2 13.7 15.7 55.9 13.1 51.9 294
e444feb210ce2096e565fb0613f98d04f2d97f91 APSL-1.1 15735 13.1 16.0 13.8 16.2 57.1 13.4 50.2 313
a19d874fcde9c037e40cd41916697ac5aac2e220 APSL-1.2 15603 13.1 16.1 13.9 16.2 57.6 13.4 50.0 312
b64068ced2da810cdadd07ac9053c192271e0a56 APSL-2.0 15945 12.4 15.4 14.0 15.4 56.0 12.8 52.2 305
c11ec559ebca765ba8f8d16634e288cdc75dff81 Artistic-1.0-cl8 3689 11.7 13.8 13.9 14.0 55.0 12.1 51.8 71
bcd8b4d1a1af706aaa1337811786a9dc6673c822 Artistic-1.0-Perl 4308 12.6 14.8 13.6 15.0 57.1 12.6 49.9 86
17c9069548d063de8fefb58b995be99c1d08bd45 Artistic-1.0 3421 11.6 13.7 14.0 13.8 54.8 12.0 52.2 65
8e42910d467b06d6af9a008678122dc61a245fcc Artistic-2.0 6949 13.1 16.1 14.5 15.4 60.7 12.8 48.3 143
d82c8eb2abc453fbd4a56aca46b22fe9fdad780d BitTorrent-1.0 19085 20.9 25.7 14.2 24.3 79.0 17.2 27.7 688
d183df8131a7114052fc3c3de647dca5fbdcb79a BitTorrent-1.1 22188 12.3 14.4 14.3 15.5 56.9 13.3 48.9 453
f45386af24b0d36976c96eac8baf5d205bed1570 BSD-2-Clause-FreeBSD 1240 11.5 18.5 16.5 15.2 66.3 12.1 62.9 19
a61e0646333b20301525695918aae3656344f611 BSD-2-Clause-NetBSD 1137 10.2 17.3 16.4 14.1 61.6 11.4 68.2 16
0fa6c43e2345f4768176f63ad24e469b832a40ac BSD-2-Clause 1046 12.3 20.3 16.5 16.1 68.0 11.9 63.8 16
cab0ab541f4f5f1ecf493b9259617df33dcbfa3d BSD-3-Clause-Clear 1372 11.5 18.1 15.9 14.9 64.8 11.8 63.3 21
54f1eeb17a7341ea0a0261a59bc5170b23137eb9 BSD-3-Clause 1200 12.5 20.0 16.3 16.0 68.2 12.0 61.5 19
f579ecea35ef059d706b32108097a960990b777d BSD-4-Clause 1325 11.9 18.0 17.0 15.5 65.1 12.8 57.0 23
837b0df8f4d995591d45c939cf567d6db8ba03d8 BSD-4-Clause-UC 1448 11.9 17.9 17.3 15.9 65.3 13.4 55.7 25
388fa291da4bd074a17d7b33334696eb71bf5ff8 BSL-1.0 1084 21.8 29.1 14.5 25.3 87.3 15.8 33.0 32
0302aaced8d1dbe1916fa0281c6a717069fda16f CATOSL-1.1 15220 15.6 18.9 15.3 19.3 65.0 15.7 38.1 399
74286ae0dfea38c489437bf659b209737945145c CC0-1.0 5116 16.2 19.5 15.0 19.5 66.3 15.6 36.8 139
c766cc6d5e63277e46a3d83c6254e3528082587b CC-BY-1.0 8867 12.6 15.5 14.1 16.4 57.8 13.8 51.3 172
bf23729bec8ffd0de4d319fb33395c595c5c762b CC-BY-2.0 9781 12.1 14.9 14.3 16.1 56.7 13.7 51.9 188
024bb6d37d0a17624cf532bd14fbd42e15c5a963 CC-BY-2.5 9867 11.9 14.7 14.2 15.8 56.3 13.6 52.6 187
20dc61b94cfe1f4ba5814b340095b4c3fa23e801 CC-BY-3.0 14956 16.1 19.4 14.1 20.4 66.1 16.2 40.0 373
e0c4b13ec5f9b5702d2e8b88d98b803e07d65cf8 CC-BY-NC-1.0 9313 13.2 16.2 14.3 17.0 59.3 14.1 49.3 188
970421995789d2e8189bb12071ab838a3fcf2a1a CC-BY-NC-2.0 10635 13.1 16.1 14.6 17.2 59.5 14.4 48.1 221
08773bb9bc13959c6f00fd49fcc081d69bda2744 CC-BY-NC-2.5 10721 12.9 15.8 14.5 16.9 59.0 14.2 48.9 219
9639556280637272ace081949f2a95f9153c0461 CC-BY-NC-3.0 15732 16.5 19.9 14.1 20.8 67.2 16.4 38.7 406
9ab2a3818e6ccefbc6ffdd48df7ecaec25e32e41 CC-BY-NC-ND-1.0 8729 12.7 15.8 14.4 16.4 58.6 13.8 51.0 171
966c97357e3b529e9c8bb8166fbb871c5bc31211 CC-BY-NC-ND-2.0 10074 13.0 16.1 14.7 17.0 59.7 14.3 48.8 206
c659a0e3a5ee8eba94aec903abdef85af353f11f CC-BY-NC-ND-2.5 10176 12.8 15.9 14.6 16.8 59.2 14.2 49.3 206
ad4d3e6d1fb6f89bbd28a44e263a89430b575dfa CC-BY-NC-ND-3.0 14356 16.3 19.7 14.1 20.5 66.8 16.2 39.7 361
39b2ef67be9e5b4e743e5269a31ad1691515eede CC-BY-NC-SA-1.0 10228 13.3 16.3 14.2 17.0 59.7 14.2 48.4 211
5800ac2d32e35ace035cdcae693423cd9ff5bb6f CC-BY-NC-SA-2.0 11927 13.3 16.2 14.7 17.1 60.0 14.4 47.0 253
e5f44c2df6b1391d1ddb6efb2db6f90670e4ae67 CC-BY-NC-SA-2.5 12013 13.1 16.0 14.6 16.9 59.6 14.2 47.7 251
a63b7e81e7b9e30df5d253aed1d2991af47992df CC-BY-NC-SA-3.0 17134 16.4 19.7 14.2 20.6 67.0 16.3 38.8 441
e4851120f7e75e55b82a2c007ed98ffc962f5fa9 CC-BY-ND-1.0 8280 12.3 15.5 14.3 16.1 57.9 13.6 52.4 158
f1aa9011714f0f91005b4c9eb839bdb2b4760bad CC-BY-ND-2.0 9228 11.9 14.9 14.5 15.8 56.9 13.5 52.7 175
5f665a8d7ac1b8fbf6b9af6fa5d53cecb05a1bd3 CC-BY-ND-2.5 9330 11.8 14.7 14.4 15.6 56.5 13.4 53.2 175
3fb39a1e46419e83c99e4c9b6731268cbd1591cd CC-BY-ND-3.0 13591 15.8 19.2 14.1 20.0 65.6 15.9 41.2 329
dda55573a1a3a80d294b1bb9e1eeb3a6c722968c CC-BY-SA-1.0 9779 13.1 16.1 14.2 16.8 59.1 14.0 49.5 197
9cceb80d865e52462983a441904ef037cf3a4576 CC-BY-SA-2.0 11044 12.5 15.3 14.4 16.2 57.9 13.8 50.2 220
662ca9fce7fed61439fcbc27ca0d6db0885718d9 CC-BY-SA-2.5 11130 12.3 15.0 14.4 16.0 57.5 13.6 50.9 218
4a5bb64814336fb26a9e5d36f22896ce4d66f5e0 CC-BY-SA-3.0 17013 16.4 19.8 14.1 20.5 67.2 16.2 38.9 437
238de92eb09c2e33e4e5fb438fe578fe5179276b CDDL-1.0 12605 11.6 13.9 14.9 14.7 55.1 12.9 50.4 250
8c7adc36e1b6f20e0cfa5fc40cefe6a427fb2cb6 CDDL-1.1 13407 12.0 14.4 15.0 15.1 56.0 13.2 49.5 270
46ebe8c487ec3e321842ed1325d98d757f965e14 CECILL-1.0 14796 11.9 12.3 11.1 15.5 51.1 13.3 53.4 277
052845a59dca83a104558addc1fdfb2cff82d328 CECILL-1.1 15874 12.0 14.1 14.3 15.4 54.3 13.4 49.9 318
c8ddd94454934cb1869ef96bddc93ff44039c591 CECILL-2.0 15163 13.2 14.0 11.1 17.0 55.0 14.1 49.9 303
04e73e027c1f47dbf743cb013480bbc974e3a8c3 CECILL-B 15337 13.4 14.2 11.3 17.1 55.5 14.2 49.2 311
1308e5090e66dcba2e594950dc4a8021551fa540 CECILL-C 15646 13.9 14.7 11.0 17.7 56.2 14.5 48.0 325
10ae2b5540f376c8cac9ccedc38ddc3435207efa ClArtistic 4511 12.5 14.8 14.0 14.8 57.3 12.6 49.6 90
cebccd48cf2bad04b29e863c564d8fd1c1f5ee15 CNRI-Python-GPL-Compatible 3172 13.0 17.8 15.6 16.2 62.1 13.1 52.7 60
18756dcb45d9598b5281368a7d35cd5e9a88306b CNRI-Python 2699 12.0 16.4 14.0 15.1 59.0 12.1 59.0 45
4bb47f04bcd1c7afb44ceb13c3bd2f62b9e0af6e Condor-1.1 4855 12.3 16.1 16.0 14.8 59.8 12.6 50.5 96
a4ece6afe1e4e92ba5985bba6f1ce76d2ee24dbb CPAL-1.0 22039 12.7 14.7 14.4 16.2 56.2 13.9 47.0 468
433089094810035bd296b27931ff68464676ed5b CPL-1.0 9273 14.8 18.1 16.6 18.3 63.6 15.3 37.7 245
251beebfa122c0c58abf32bb8224e1b9ebb6db59 CPOL-1.02 9216 10.7 13.1 13.1 14.0 49.9 12.1 59.5 154
a529e9bff1eb4f976a9bf1eb3ef8054e52967a91 CUA-OPL-1.0 18086 12.1 14.3 14.3 15.3 55.0 13.3 49.6 364
0a5785a9fe34a8f779ee79f8333ee766d5c0676e D-FSL-1.0 12123 11.4 14.0 17.2 13.9 49.2 12.5 45.1 268
04ed6736b16995b2bbd3fd7b4fb1cb6efa44b6a6 ECL-1.0 1949 15.2 18.9 15.6 19.4 67.7 15.8 40.2 48
2a3706dec618b5198ba177691bbf30d97becc7a8 ECL-2.0 8955 17.0 20.0 15.2 20.9 65.4 16.8 32.5 275
8d7c74721fac21d583f9bffafb5747ad6994f695 eCos-2.0 1148 11.0 12.7 11.2 14.0 49.4 11.7 60.7 18
7b8021b0d18d9fd4f5ac7bac3a5584c9fb4d5966 EFL-1.0 521 6.6 13.1 14.9 9.6 58.0 7.9 83.3 6
530270003ac19b54a548e13b08108c1abf166a09 EFL-2.0 630 6.3 11.5 14.4 8.7 56.6 7.6 81.0 7
a3ce248131ee7e9eca19460ddd1c7858350aed9e Entessa 1827 9.8 15.1 17.0 12.8 59.5 11.4 61.2 29
11fadbd49466127930da08f01fea6c803dc8c462 EPL-1.0 9028 14.6 17.9 16.6 18.1 63.4 15.2 38.5 234
5a46ff9626e703387228d6de1d695ce9d8d47931 ErlPL-1.1 11028 11.9 14.1 14.2 15.2 54.6 13.1 50.5 218
9098acfa2c2b7780da7d3644faa81df5a44a0536 EUDatagrid 2605 14.0 19.8 18.0 17.6 69.3 14.5 45.0 57
4654cbafc6474f59de1234a11eb6462a02aaffe6 EUPL-1.0 9821 12.6 13.8 13.5 16.4 54.1 14.1 46.5 211
2aeeba8e44c78afd0b9064a43a277158cb018227 EUPL-1.1 10047 12.6 13.8 13.7 16.4 54.3 14.1 46.3 216
5c18b40cb5bbd57b858a2e2827fc89d66e202894 Fair 209 4.5 8.2 15.0 7.0 42.5 7.7 80.4 2
bded6d45d800403709fa630a58c0f1d68e3365e7 Frameworx-1.0 7536 17.4 22.0 16.3 21.5 72.4 17.0 33.4 225
f3a7b9a82d2cecb0edcf57d7d8aa0e37f6fcde66 FTL 4580 10.2 12.4 13.8 13.2 53.1 11.8 57.9 79
579a1d52e08b7a09429df7f7651dd3ef747727c7 GFDL-1.1 14318 12.5 14.4 13.5 15.4 56.1 13.1 49.9 286
eb670eaf7269bf3cb8990a52b05618e5dbd963b6 GFDL-1.2 16124 12.3 14.2 13.6 15.4 55.7 13.2 50.1 321
394dbacde4c26a5f58c9823e25ef6e937eba75a3 GFDL-1.3 18147 12.6 14.6 13.5 15.8 56.1 13.4 49.3 368
21d887b87b4297c5b6eea0c300b77ee8b3f8337d GPL-1.0 9288 12.2 14.9 12.2 15.1 54.6 12.1 57.4 161
21d887b87b4297c5b6eea0c300b77ee8b3f8337d GPL-1.0+ 9288 12.2 14.9 12.2 15.1 54.6 12.1 57.4 161
0473f7b5cf37740d7170f29232a0bd088d0b16f0 GPL-2.0 13664 13.3 16.2 12.5 16.2 57.0 12.7 52.9 258
80c08b24ac7e98376c0c387a1890a283e9c5ffe0 GPL-2.0+ 13664 13.3 16.2 12.5 16.2 57.0 12.7 52.9 258
3a9262b9d066ce5d41feb871b1f786336a20628b GPL-2.0-with-autoconf-exception 1313 12.0 13.8 12.9 14.7 53.5 12.5 52.8 24
86084a36e75fb92c36082dd61ac812495446f6d8 GPL-2.0-with-bison-exception 561 18.3 20.7 12.7 21.0 64.5 15.6 32.7 17
be15f8fcc097be4db1cfef6f469108b4364db84e GPL-2.0-with-classpath-exception 785 13.2 14.9 12.7 16.7 55.4 14.0 48.4 16
3cddc56f4cb24809cabd4af80ce3d3bda97152f8 GPL-2.0-with-font-exception 492 12.5 13.3 10.3 16.9 51.2 14.0 55.2 8
22ece69587f935f0bf61df00cec4b2c4f73163f7 GPL-2.0-with-GCC-exception 283 24.7 30.3 15.1 29.0 87.3 20.3 14.2 19
d4ec7d0b46077b89870c66cb829457041cd03e8d GPL-3.0 27588 13.7 16.0 13.3 16.8 57.5 13.8 47.2 584
d4ec7d0b46077b89870c66cb829457041cd03e8d GPL-3.0+ 27588 13.7 16.0 13.3 16.8 57.5 13.8 47.2 584
a0ac5d9bc70d97d2f2068f87779aa9fe35368dd8 GPL-3.0-with-autoconf-exception 1460 10.3 12.0 14.1 13.5 51.5 12.2 55.5 26
3d7d507c4df41892664f128b810daf0131e0b817 GPL-3.0-with-GCC-exception 2716 13.4 15.1 15.2 16.3 58.5 14.0 40.6 66
36f65f578919826062bffcca2557317294953ad3 gSOAP-1.3b 15881 10.6 14.1 14.3 13.8 55.2 11.9 59.5 266
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License

Original files in this project are disjunctively licensed under all licenses in the SPDX licenses list 1.19 (215) and those included in licenses-other (13). Take your pick of any or all.

License texts purport to be under various terms; see each individual license text.

3 Responses

  1. […] Chars/(Flesch>=1), the latter being my gross metric for how painful it is to read a document; see license automated readability metrics for an […]

  2. […] best modern permissive license for software (Apache 2.0) is relatively long and unreadable for what it does, and has an discomfiting name (not nearly as bad as certain pro sports […]

  3. […] of Flesch; Chars/(Flesch>=1) is my gross metric for how painful it is to read a document; see license automated readability metrics for an […]

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