Hello ! I have encountered the same problem described in bug #9804: "The result of an intersection is sometimes equal to one of the input polygons, when the result should be empty". https://svn.boost.org/trac10/ticket/9804 Does anyone knows if this bug was fixed and in which boost version ? Is there any version release notes related to this bug ? Alternatively, does anybody know what cause this problem ? Thanks Michael *********************************************************************************************** Please consider the environment before printing this email ! The information contained in this communication is proprietary to Israel Aerospace Industries Ltd. and/or third parties, may contain confidential or privileged information, and is intended only for the use of the intended addressee thereof. If you are not the intended addressee, please be aware that any use, disclosure, distribution and/or copying of this communication is strictly prohibited. If you receive this communication in error, please notify the sender immediately and delete it from your computer. Thank you. Visit us at: www.iai.co.il