What are some marketing agencies specializing in marketing b2b SaaS apps?

Can second the Inturact recommendation. My one piece of advice making this search is to make sure the people you're talking to are true specialists. A great test is to ask them SaaS specific questions in your first call with them (e.g. "What are your thoughts on per user pricing for companies like ours?"). There's lots of marketing agencies out there that have used SaaS as a keyword/marketing strategy themselves, who don't really have any deep expertise. They just deliver the same stuff as all the other marketing agencies out there. One of my colleagues, Ryan, wrote a blog post to help SaaS companies looking for a marketing agency (it's inbound specific, but applies to any marketing agency search): http://www.cobloom.com/blog/6-challenges-youll-encounter-hiring-an-inbound-marketing-agency

http://www.newbreedmarketing.com/ is a HubSpot Diamond Partner that specializes in marketing and sales for B2B SaaS companies. Here are some of their SaaS specific resources that you might find helpful: http://www.newbreedmarketing.com/blog/marketing/saas-marketing-guide http://www.newbreedmarketing.com/blog/marketing/marketing-goals-calculator-template http://www.newbreedmarketing.com/blog/marketing/lifecycle-marketing-strategy http://www.newbreedmarketing.com/blog/marketing/saas-marketing-cohort-analysis http://www.newbreedmarketing.com/blog/marketing/saas-lead-generation-strategies http://www.newbreedmarketing.com/saas-marketing Disclaimer: I work there.

If you're looking for a marketing agency for a bootstrapped startup, you should definitely consider an agency with "bootstrap" in their name. In all seriousness, http://bootstrap-mktg.com/  and Business Developent is a high-tech marketing agency located in San Carlos, CA.  The team is made up of tech industry professionals with deep knowledge and experience with software and Big Data.

http://www.inturact.com/ specializes in B2B Product & SaaS Marketing. Once you've found product market fit I would recommend giving them a call to build your marketing machine. There is also tons of great info on Lincoln Murphy's blog http://sixteenventures.com/ - http://sixteenventures.com/

Orange Pegs Media (http://www.orangepegs.com)  is an inbound marketing agency from Orange County that specializes in both SAAS and start-ups. Check out their respective write-ups here: http://www.orangepegs.com/b2b-saas-marketing-strategy-customized-like-your-software http://www.orangepegs.com/startup-marketing-plan-that-helps-you-grow They'll build your strategy, help you find the right tools, and drive the program with your involvement - as heavy or as light as you can manage and afford.

Genesis Burson-Marsteller. It is one of the most famous Marketing Agencies. http://www.genesisbm.in/

http://www.brightinfo.com