“First In, Still Here” (FISH) is an infrequently used accounting acronym, similar to “First in, First Out” (FIFO) and “Last In, First Out” (LIFO). FISH has been cited in print since at least 1974. A 1977 book credited the erm “FISH” to accounting professor George H. Sorter.
   
   
Investopedia
DEFINITION of ‘First In, Still Here - FISH’
An accounting buzzword that describe when companies still have inventory on hand that is not being sold due to inattention or obsolescence. While not an official type of accounting treatment, the term is named after the LIFO and FIFO accounting methods.
 
24 October 1974, Women’s Wear Daily, “The Fabrics: Fiber industry moving to finer-denier yarns” by Marvin Klapper, pg. 27:
He noted that some fiber producers were shifting from LIFO accounting procedure to FIFO, and the resultant slowdown had created a new classification, FISH—first in, still here.
 
27 November 1974, Traverse City (MI) Record-Eagle, “New inventory method popular” by Alan Abelson (Dow Jones-Ottaway Service), pg. 10, col. 7:
The trickle of companies switching from the FIFO method of evaluating inventories to the LIFO method is rapidly becoming a flood. Our good friend Laura Sloate incidentally, relays the conjecture that in view of the way business is going a more appropriate accounting acronym for such purposes may be FISH—Fish in-still here.
 
Google Books
Accounting for Lawyers
By E. McGruder Faris and A. L. Shugerman
Indianapolis, IN: Bobbs-Merrill
1975
Pg. 135:
For example, under LIFO, we are really counting on the basis of “first in, still here” (FISH) ; and under FIFO we are really counting on the basis of “last in, still here” (LISH). While FISH and LISH may aid the understanding of some readers, they are not often used in accounting literature.
   
Google News Archive
25 January 1975, Milwaukee (WI) Sentinel, “Economy Is Torn Loose” by Ray Kenney, pt. 2, pg. 7, col. 4:
FIFO and LIFO? You’ve heard a lot about it, one corporate financial officer suggests. But how about FISH? first In, Still Here?”
 
Google Books
Accounting:
The Language of Business (Third Edition)
By Sidney Davidson, Roman L Weil, James S. Schindler and Clyde P. Stickney
Glen Ridge, NJ: Thomas Horton and Daughters, Incorporated
1977
Pg. 25:
FISH An acronym, conceived by George H. Sorter, for first-in, still-here. FISH is the same cost flow assumption as LIFO. Many readers of accounting statements find it easier to think about inventory questions in terms of items still on hand. Think of LIFO in connection with cost of goods sold but FISH in connection with ending Inventory. See LISH.
 
Google Books
Probability, Statistics, and Queueing Theory:
With Computer Science Applications
By Arnold O. Allen
San Diego, CA: Academic Press, Inc.
1990
Pg. 325:
These include BIFO (biggest-in, first-out).15, FISH (first-in, still- here), and WINO (whatever-in, never-out) The reader can, no doubt, think of others to describe personal experiences with queueing systems.
 
Google News Archive
5 July 1992, New Straits Times (Malaysia), “Key factors in making of star sales manager” by Philip Wee (PA Consulting Group), pg. 30, col. 6:
What if we run into the “First In, Still Here” (FISH) problem with Product X?
 
Google Books
Managerial Accounting:
An Introduction to Concepts, Methods and Uses
By Michael W. Maher, Clyde P. Stickney and Roman L. Weil
Mason, OH: South-Western
2012
Pg. 545:
FISH An acronym, conceived by George H. Sorter, for first-in, still-here. FISH is the same cost flow assumption as LIFO. Many readers of accounting statements find it easier to think about inventory questions in terms of items still on hand. Think of LIFO in connection with cost of goods sold but FISH in connection with ending Inventory. See LISH.