Though my company had other options apart from Coverity, we chose to continue with Coverity as we were already using it for some projects in our organization.

In addition to Coverity, I have experience with Checkmarx, Fortify, Veracode, and HCL AppScan, which was previously known as IBM AppScan.

Checkmarx is probably the most extensible and customizable of these products, and you're able to use the C# language to do so, which a lot of developers are familiar with.

HCL AppScan is another tool that has customization capabilities. They are not as powerful but they are easier to implement because you don't need to write any code.

I cannot give an endorsement for any particular one. They all have their merits and it just depends on the requirements. Generally, however, all of these tools are getting better.

Before choosing, we tried to use gcc compiler options, i.e. 

EXT_GCOV_FLAGS='-fprofile-arcs -ftest-coverage'
EXT_GCOV_LDFLAGS=-fprofile-arcs
EXT_CC_FLAGS=-fdiagnostics-show-option
GCOV_LIB=-lgcov

Our license for Coverity has expired and we are in the process of exploring new static code analysis tools. Ideally, we would like to have one that is low-cost.

One of the products that I have downloaded a trial version for is SonarQube. At this point, I have only installed the Windows version but I plan on testing the Linux version, as well.

This solution seemed to fit our purposes.