Red stamps have, in fact, the same function as the seals used for 'Untersiegelung', namely to authenticate a document. A first type of document on which they are attested is petitions from the Ptolemaic Era, originally from the Hermopolite and the Herakleopolite Nomes. Once arrived at the office of the strategos, the official at the head of a nome, some petitions received a red stamp. This was usually put on the recto of the papyrus in the upper left corner and sometimes covers part of the text of the petition [see List Nos. 266, 271-282].

The remaining red stamps are all found on late Ptolemaic (130)  and Roman documents from the Fayum (Arsinoite Nome), mainly from the metropolis Ptolemais Euergetis. They are all documents drawn up or registered by an official: contracts drafted or registered in the record office (grafei~on) (131)  and bank receipts, mainly for tax on sales (132).  The red stamps appear on the verso of such documents. Several of these texts have more than one stamp (133).  The red stamp was called cavragma  (134) and was placed on the document by the official responsible for the stamping (135).  The purpose of those stamps was to legalize a document (136).  Below some of the stamps, an official has written "I, NN, have marked (seshmeivwmai)" (137).

There is an evolution in the characteristics of the red stamps of the Fayum. The Ptolemaic red stamps  (138) all have the regnal year in the middle, surrounded by a rosette or by the name of the king (Ptolemaios), which makes up a circle [see Figure 12; see Plate]. None of the Roman red stamps seems to have the regnal year in the middle. There are different types, usually of round shape (139).  The early examples  (140) have Gr (for grafei~on, record office) in the centre, surrounded by the regnal year and the name of the emperor, which makes up a circle [see Figure 13]. A later example  (141) has the text (regnal year and name of the emperor) in a spiral. From the end of the first century A.D. onwards (142)  stamps usually consist of two circles: the outer circle has the regnal year and part of the title of the emperor(s); the inner circle continues the emperor's title; the middle of the two circles has Gr (for grafei~on) or shows the bust of the emperor [see Figure 14].

One original stamping object from Egypt has been preserved [see List No. 287]. It is a stamp in the museum of Berlin and dating to 5/6 A.D. The text reads, naturally, as a mirror image and the stamp still contains traces of red ink (see Plate).