DWG files - which version of AutoCAD?

Scenario:
You have been sent a dwg to work on and must send it back in the same format it was received, but you do not know which version of AutoCAD it was last saved in.

Solution:
- Right-click on the DWG and Open With Notepad
- Read the first 6 characters and match them to the following versions:

AC1027 - AutoCAD 2013, 2014, 2015
AC1024 - AutoCAD 2010, 2011, 2012
AC1021 - AutoCAD 2007, 2008, 2009
AC1018 - AutoCAD 2004, 2005, 2006
AC1015 - AutoCAD 2000, 2001, 2002
AC1014 - AutoCAD Release 14
AC1013 - AutoCAD Release 13
AC1009 - AutoCAD Release 11, 12
AC1006 - AutoCAD Release 10
AC1004 - AutoCAD Release 9
AC1003 - AutoCAD 2.6
AC1002 - AutoCAD 2.5

You can now save back to the nearest format.

SC

Import and Export Formats in Inventor 2011

A question that comes up often on support is what formats we can open into Inventor and those formats we can save to. Therefore we have put together some information in reference to this below for all to see:

Format	Import	Export
AutoCAD 2D/3D (*.dwg, *.dxf)	R12-2011	R12-2011
Alias (*.wire)	all versions	-
CATIA V4 (*.CATPart, *.CATProduct, *.model)	all versions	-
CATIA V5 (*.CATPart, *.CATProduct)	R6-R18	R10-R18
IGES (*.igs)	all versions	5.3
JT Precise (*.jt)	7.0, 8.0, 8.1, 8.2, 9.0, 9.1, 9.2, 9.3. 9.4	7.0, 8.0, 8.1, 8.2, 9.0, 9.1, 9.2, 9.3, 9.4
NX (*.prt)	3-6 (7 in SAP)	-
Parasolid (*.x_b, *.x_t)	up to ver 22.0	9.0-22.0
Pro/ENGINEER (*.prt, *.asm)	up to ver 5.0	-
Pro/ENGINEER Granite (*.g)	up to ver 6.0	1.0-6.0
Pro/ENGINEER Neutral (*.neu)	all	all
SAT (*.sat)	4.0-7.0	4.0-7.0
SolidWorks (*.prt, *.sldprt, *.asm, *.sldasm)	2003-2010	-
Rhino (*.3dm)	(in SAP)	-
STEP (*.stp, *.ste)	AP214, AP203E2	AP214, AP203E2
STL (*.stl)	-	all
XGL/ZGL (*.xgl/*.zgl)	-	all