From top to bottom, this seal contains the letters LCM, then a 4-winged serpent icon, then a double line, then the letters $PNYEU (והינפצ מסל can be transliterated as "Belonging to Sam Zephaniah").  Some dispute exists over one or two additional letters that may have been engraved between the upper & lower wings of the icon leading to the following possibilities:

K on the left (והינפצ ךמסל = "Belonging to Samak Zephaniah")

Y on the right, K on the left (והינפצ ךי מסל = "Belonging to Samik Zephaniah")

K on the right, Y on the left (והינפצ יכ מסל = "Belonging to Samky Zephaniah")

B on the right, N on the left (והינפצ ןב מסל = "Belonging to Sam, son of Zephaniah"

K on the top, B on the right, N on the left (והינפצ ןב ךמסל = "Belonging to Samek, son of Zephaniah"

Another dispute exists over whether there were one or two seals made for the same person with the same icon, which would account for some of the diverse interpretations.

The Biblical prophet, Zephaniah, lived during the reign of King Josiah; so it's highly unlikely that the name on this seal refers to a relative of him since these handles with Personal seals date to Hezekiah's reign (at least 55 years before Josiah).  In fact the genealogy listed in Zephaniah 1:1 indicates that the prophet may have been a descendant of King Hezekiah.