[tz] leap_second.list not updated after latest IERS Bulletin C

Brian Inglis Brian.Inglis at Shaw.ca
Sat Dec 9 20:47:33 UTC 2023

On 2023-12-08 15:04, Brooks Harris via tz wrote:
> On 12/8/2023 3:58 PM, Paul Eggert wrote:
>> On 2023-12-08 11:58, Brooks Harris via tz wrote:
>>> anything from IERS must be public domain, isn't it? How is it not?
>> It’s published in France and French law does not recognize the US notion of 
>> public domain. The French “domaine public” is more restrictive than the US 
>> notion, and as I understand things if published in France the file cannot be 
>> domaine public anyway; that can happen only 70 years after publication.
>> The IERS version lacks a copyright notice, and it’s not clear who holds the 
>> copyright or under what terms TZDB could legally reproduce the file. The 
>> copyright holder might be the IERS, the Paris Observatory, Paris Sciences et 
>> Lettres University, the Ministry of National Education, or some other body. A 
>> while ago I asked for a proper copyright notice to be added, to clarify rights 
>> and establish permissions, but this has not gotten anywhere presumably because 
>> the people in charge of the IERS version are busy and don’t think this is 
>> important.
>> Given the legal uncertainty it’s safer for TZDB to not copy the IERS version.
> Thanks.
> As far as I can tell there is no "leap-seconds.list" file at IERS. This NIST 
> file appears to be a reconstruction of the IERS leap-second data, either 
> assembled from Bulletin C, or transposed from the "Leap_Second_History.dat" file 
> at https://hpiers.obspm.fr/eoppc/bul/bulc/Leap_Second_History.dat.

On most leap seconds sites, leap-seconds.list is usually a symlink to 
leap-seconds.NTPTIME, where NTPTIME is usually the integer NTP time stamp at 0Z 
on the date of the most recent bulletin C, or the local issue date e.g.

$ curl ftp://hpiers.obspm.fr/iers/bul/bulc/ntp/
-rw-rw-r--    1 ftp      ftp           540 Jul 06  2016 README
-rw-rw-r--    1 ftp      ftp          4928 Apr 03  2015 leap-seconds.3637008000
-rw-rw-r--    1 ftp      ftp          4928 Jul 07  2015 leap-seconds.3645216000
-rw-rw-r--    1 ftp      ftp          4927 Sep 16  2015 leap-seconds.3651350400
-rw-rw-r--    1 ftp      ftp          4928 Jan 11  2016 leap-seconds.3661459200
-rw-rw-r--    1 ftp      ftp          4928 Jan 13  2016 leap-seconds.3661632000
-rw-rw-r--    1 ftp      ftp          4920 Jul 06  2016 leap-seconds.3676752000
-rw-rw-r--    1 ftp      ftp          4925 Jan 19  2017 leap-seconds.3693772800
-rw-r--r--    1 ftp      ftp          4921 Jul 07  2017 leap-seconds.3708374400
-rw-r--r--    1 ftp      ftp          4923 Jan 09  2018 leap-seconds.3724483581
-rw-r--r--    1 ftp      ftp          4921 Jul 05  2018 leap-seconds.3739787886
-rw-r--r--    1 ftp      ftp          4949 Jul 04  2019 leap-seconds.3771235866
-rw-r--r--    1 ftp      ftp          4953 Jan 07  2020 leap-seconds.3787382231
-rw-r--r--    1 ftp      ftp          4949 Jul 07  2020 leap-seconds.3803144275
-rw-r--r--    1 ftp      ftp          4953 Jan 07  2021 leap-seconds.3819011916
-rw-r--r--    1 ftp      ftp          4949 Jul 05  2021 leap-seconds.3834432000
-rw-r--r--    1 ftp      ftp          4953 Jan 05  2022 leap-seconds.3850377469
-rw-r--r--    1 ftp      ftp          4949 Jul 05  2022 leap-seconds.3865995417
-rw-r--r--    1 ftp      ftp          4953 Jan 09  2023 leap-seconds.3882249427
-rw-r--r--    1 ftp      ftp          4949 Jul 04 13:06 leap-seconds.3897417600
lrwxrwxrwx    1 ftp      ftp            23 Jul 04 13:06 leap-seconds.list -> 
drwxr-xr-x    2 ftp      ftp          4096 Apr 03  2015 sources


and the other Bulletin C data:


> The NIST file does not appear to explicitly say its in the "public domain". But, 
> as I understand it, anything NIST says, does, or publishes is in "public domain" 
> as far as USA law goes. Hopefully this just remains a matter of my inexpert 
> curiosity.

Other referring documents remind users that most documents and data on sites are 
in the public domain in the US:


Take care. Thanks, Brian Inglis              Calgary, Alberta, Canada

La perfection est atteinte                   Perfection is achieved
non pas lorsqu'il n'y a plus rien à ajouter  not when there is no more to add
mais lorsqu'il n'y a plus rien à retirer     but when there is no more to cut
                                 -- Antoine de Saint-Exupéry

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