This is a very long thing to read but was very interesting. What caught my eye was the part about DOT #'s near the end of the article in section H. Here is a link:

http://www.costatech.com/Costa_Technologies_Home_Page.htm
Click on Safety Regulations and then on Safety Legal Status- both on the left side of screen. Then in the center of the screen click on the ANS Z-26.1-1977 and Z26.1-a-1980.

The whole thing is pretty interesting. From what I read in other area's online there was or is suppose to be a ruling between 9/06 to 11/06 as PPG, GM, Visteon and others sent in a petition on Standard 205.

Here is what is said about DOT #'s:

H. Verification of DOT Numbers

Paragraph S6.2 of Standard No. 205 requires that the prime glazing
manufacturer mark the glazing with, among other things, a
manufacturer's code mark. The mark is assigned by us upon the written
request of the manufacturer. We maintain a list of glazing
manufacturers and the marks assigned to them. One use of these code
marks (often referred to as a ``DOT number'') is during an enforcement
action to identify the manufacturer that produced a particular piece of
glazing.
The SAE Glazing Standards Committee is concerned about the accuracy
of our Glazing Manufacturers list. Only 25 percent of the manufacturers
listed with DOT numbers are currently active, according to the SAE. SAE
further contends that some of the manufacturers have gone out of
business without notifying us and that many other manufacturers have
moved or merged. Moreover, SAE believes that some of these DOT numbers
are being improperly used.
Therefore, we are requesting comments on the need to verify the DOT
numbers.

WOW!!!! Maybe all this tracking of DOT#'s I have been doing for 3 years will finally pay off??

Or then again, maybe not. This is the U.S. government telling us they do not have accuarate records.

Does anyone else track the DOT# of the previous windshield or the DOT# of the windshield you are repairing?