What does this one mean? (Stars on boxcars)

I'm familiar with the white star next to the LD LMT weight on freight cars. AAR rule 30 says such marked cars can only be weighed by the home road or owner. No problem there. However, I've seen two photos of NYC boxcars that have a 9", 5-pointed star between the NYC oval and the dimensional data. One is on NYC 132579, lot 668B, photo taken in 1951, and the other is on NYC 168770, lot 773B, an all red Pacemaker car, the photo taken in 1954. There are no special instruction stencils on either car. What does this star mean?
Thanks in advance,
Ed Byrnes

Could be an exparimental paint sceam that never took on. Or they Maybe the cars were painted up as "Buy War Bonds" Cars? I had seen sevral photos of cars with small white stars on railcars befor and were mostley trying to get people to buy War Bonds during WWII. I have also seen the same thing done on a Conrail Boxcar during the Gulf War I saw the car once but never thought to sanp a pic of it at the time

I found the following note on the Canada Southern website http://www.canadasouthern.com/caso/photo.htm. There is also a picture of boxcar 175000 with such a star.

"A STAR under the herald was suppose to denote a car that was not to be sent off line ( per Charles Smith - NYCSHS - Third Quarter 1995 Headlight). In addition to this, based on an article in the December 1947 Headlight, there was a major shortage of freight cars, primarily boxcars, and this may have been in an effort to keep cars online to continue to provide enough cars for NYC customers ( please note that this is NOT specifically stated in the article). Since this shortage was from 1945 to around 1949, most cars having this star were built or rebuilt during this same period of time. During these years, cars were being retired ( due to being worn out by extreme war time demands on the fleet ) at a faster rate than new cars could be built and at the same time freight traffic was at an all time peace-time high, resulting in a critical shortage of cars during these years - this was a nationwide crisis - not a NYC only situation, so this may have been a NYC effort to keep a supply of cars on hand for their own customers. Once the shortage of cars ended, these cars roamed off home rails."

In regard to your comment on AAR Rule 30.

The star symbol had no bearing on the light weight. It was applied only to the Load Limit and in some cases also the Capacity. Only the car owner or his designated representative could change the Capacity and Load Limit stencils. Anyone, when necessary, could reweigh and stencil a car.

AAR Rule 30 (Interchange Rule 30) was last published in 1969. When the format for the Interchange Rules was changed in 1970 it became Rule 70.

Many thanks to NYC_Dave. That CASO web sight is great. Also my appologies to Ramcat. Even though I know what AAR 30 states, I worded my inquiry incorrectly. Thanks for the update on Rule 30 and clarifying my statement for anyone else who views this message.
Thanks again,
Ed Byrnes