Per the Blue Book of Electric Guitars, Dean's serial numbers are straight forward with the first two digits equaling the year of manufacture and the remaining numbers equaling the instrument number. So it appears you have a 1951 Dean or an import model?

Dean's Clock Collection - Some Observations Regarding Serial Numbers on Gustav Becker Clocks - with photographs. Some Observations Regarding The dating of Gustav Becker Clocks using Serial Numbers (with photographs)- DRAFT 11/2002 -Here's another link with a serial number dating chart. Worth looking at, but they mention nothing about Braunau. The 'Vintage Dean Collection' includes guitars manufactured between 1977 and 1987. Look for a distinctive serial number located on the back of the headstock. Dean guitars made in the United States have a seven-digit serial number. The first two numbers indicate the year the guitar was manufactured. Try making a post on the Dean board - lots of knowledgeable folks. For the most part - the USA models will have 'Made in the USA' with YY - SERIAL on the back of the headstock. In the late 90's (1996 I believe) the serial #'s for the USA models were stamped on the fret board after the last fret. Cool technology to make finding and buying parts a breeze, including Serial Number Lookup, PartSPIN® and Smart Manuals, found on partstown.com and our industry-leading mobile app; An exceptional customer experience from the team you know and trust with every email, live chat, text and phone call, provided by a friendly and knowledgeable team.

Some Observations Regarding
The dating of Gustav Becker Clocks
using Serial Numbers
(with photographs)

-- DRAFT 11/2002 --

Here's another link with a serial number dating chart . Worth looking at, butthey mention nothing about Braunau factory !
http://www.bhi.co.uk/hints/gbecker.htm

I have seen many people selling Gustav Becker clocks applya date to them based on the serial number on the movement. In many cases Ibelieve the dates provided may be incorrect. I'm not anexpert, nor do I claim to be. As a beginning collector of European,Austrian, & German clocks, I hate to see people be mislead intentionally oraccidentally, when there is information out there that can help.

Many people are inappropriately dating clocks made in theBraunau factory using the Gustav Becker Freiburg factory chart that iscontained within the books listed below. This yields a completely bogusdate and is false and misleading.
Please note that I am merely passing along what I see in the books listed belowand you, of course, may do with the information what you wish. I urge youto do your own research and/or consult an expert before making any expensivebuying decisions. Naturally, if anybody has better information that I do,please pass that along to me and I will happily correct anything that is inerror.

Dean Serial Number Search

The conclusions I've drawn are as follows:
1) It is relatively easy to tell on most clocks whether a clock was made inFreiburg or in Braunau by looking at the trademark stamped on the back of theclock
2) Clocks made in the GB Freiburg factory can be dated with some level ofaccuracy based on the serial number.
3) Clocks made in the GB Braunau factory cannot be dated with anyaccuracy, as the factory was possibly opened in 1888.
4) According to the books, Freiburg was making close to 100k clocks a year by1880, so one might assume that Braunau was making somewhat less than that peryear.

The 2 books I am using for reference are:
1) Gustav Becker Story - 1847-1927 - by Karl Kochmann @ 1974 1993edition ISBN 0-933396-29-5
2) Clock & Watch Trademark Index - European Origin - by Karl Kochmann@1988 ISBN 0-933396-34-1

1) Reference Book - Gustav Becker Story
Page 32, near the top
GUSTAV BECKER
Braunau - Bohemia, Former Austrian - Hungarian Danube Fed. ( now Broumov, CSR )
Gustav Becker, assembly plant since the year 1888. After the annexation ofBohemia, year 1918 * (*after ww-I)
into Czechoslovakia, Becker Clocks were marketed with the stamp: MADE in BRAUNAUTSCHECKOSLOVAKIA
....
Note: Serial number index not traceable. Plant closing year unknown.

Page 35, 3/4 of the way down the page

Braunau works - Numbering system-or index not traceable.

1) Reference Book - Clock & Watchtrademark Index
Page 293, near the bottom
GUSTAV BECKER
... ...
The Braunau works operated as independent branch factory. No serial numberrecords are found.
... ...
GUSTAV BECKER
Braunau - Bohemia
Former Austrian Danube Federation no Czechoslovakia 036/4
After annexation of Bohemia:* (after WWI) the production of the former Beckerbranch factory
was sold with embossement since 1918

Page 294,
Same chart as in 'The Gustav Becker Story', above.

Dean Fryer Serial Number Lookup

Photographsof Trademarks

Note: There are lots of different GB stamps , theseare just a few

Dean Guitar Serial Number Lookup

Example of trademark stamps with Braunau works ( SN100k+ , 500k+ )

Example of trademark stamps with Freiburg / Silesiaworks

IExample of trademark stamps with Freiburg/ Silesia works
Oddly enough, on this one, it's on the right side not the left.

Example of a very early trademark stamp with Freiburg/ Silesia works ( SN 89603k )

Example of a very early trademark stamp with Freiburg/ Silesia works ( SN 35k )

Example of a very early trademark stamp with Freiburg/ Silesia works ( SN 25k )

Having recently learned that Freiburg/Silesia is inPoland, there may be some issues in calling these 'German' clocks...but probably not.

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Not responsible for errors or inaccuracies. Forreference only, use at your own risk. Sources used are listed above.

Dean Serial Number Lookup