hi guys .. I found this info on some site.. so thought of sharing with you all: OK it goes like this..starting with Japanese built guitars: 1997 to Now F=Fujigen factory, 2nd & 3rd digit=year made(eg 04=2004) next 5 digits =month & build number Jan=5000 Feb=10000 Mar=15000 Apr=20000 May=25000 June=30000 July=35000 Aug=40000 Sept=45000 Oct=50000 Nov=55000 Dec=60000 So an example here is for a recent model with a Serial number F0330210 = Fujigen 2003 June 210th guitar built. 1984 to 1996 example serial number F232104 F=Fujigen 2=1992 as an example 3=March production So 1=Jan 12=Dec 2104 guitar built for that month 2104th made 1975 to 1983 Example serial number C800358 C=March So A=Jan M=Dec 80 = 1980 year of build 0358= 358th guitar built for that month. Sung Eum Factory Example serial number E9052345 E=Sung Eum 9=1999 05= May So 01=Jan 12=Dec 2345= 2345th guitar built for that month Korean Built Ibanez Cort Factory Acoustics and Electrics start with C eg C03071234 C=Factory 03=2003 07=July 1234=1234th guitar built for that month Saehan Factory: acoustics start with SQ, electrics start with S Sae-In Factory starts with A These other factories follow the same serial number pattern as the Cort Korean factory. Indonesian Made Ibanez These guitars start with the following I=Cort Indonesia factory K=KWO factory J=Sejung factory The example serial number is K031034335 K=KWO 03=2003 10=Oct. So 01= Jan 12=Dec 34335 it is from the Acoustic range So 00001 to 49999 are Acoustic Guitars, 50000 to 99999 are electric guitars and electric basses All 3 factories use the same serial number system China Production W=World Factory Z=Yeou Chern Factory Example Serial Number WX32149 W=World Factory X=October...but wait it goes like this for the build months 1=Jan 2=Feb 3=Mar 4=Apr 5=May 6=Jun 7=July 8=Aug 9=Sep X=Oct Y=Nov Z=Dec 3=2003 2149= 2149th guitar built for that month. u can check it at : https://www.guitardaterproject.org/ibanez.aspx