In November 1899, the post office in Jaluit, Marshall Islands, placed an order for 2,000 each of the 3 Pf (MiNr 1 I) and 5 Pf (MiNr 3 I) Marschall-Inseln overprints, as their stock was running low. These stamps were prepared for shipment from Berlin on 12-13 February 1900, and arrived in Jaluit in April 1900.
Prior to the arrival of these stamps, however, the Jaluit post office ran out of 5 pf stamps. To remedy the shortage, 10 Pf stamps were bisected for use as 5 Pf provisionals (MiNr 3 I H). It’s estimated that no more than 100 stamps were bisected in this manner.
Legitimate uses are on postcard or wrapper, not on cover. Cancels exist with dates from February to May 1900.
The copy shown above is one of only two known registered postcards with this usage. The other is Jaluit Registered #292, and was also offered at auction within the last couple months. This copy is also notable for being a non-philatelic usage, which is somewhat of a rarity with German colonial provisionals.
As far as the German colonial provisionals go, Marshall Islands MiNr 3 I H is second in catalog value (on postcard -- €30,000) only to Marshall Islands MiNr 12 H (on cover -- €45,000), a bisect from December 1900 of which only 8 copies are known to exist.