LinkedIn can be an attractive place to advertise, especially for B2B companies.

After all, you can target people by their industry, company, title, location, job skills, seniority, interests, school attended, and on and on.

You can do some pretty laser-targeted campaigns.

And I’ve built several targeted campaigns using LinkedIn’s sponsored updates, complete with videos and landing pages.

However, I’ve had mixed success.

Part of the problem is this: LinkedIn doesn’t allow you to filter out mobile traffic.

Why is that a problem?

Because, for the most part, mobile traffic doesn’t convert.

Having managed millions in Google AdWords budget across all types of industries, I’ve found that although mobile searches and mobile traffic has exploded in recent years, conversions have not.

In fact, for most of the campaigns I manage, I don’t even show ads on mobile devices – there’s just not the ROI.

Why is that?

There’s a number of factors at play:

• On a mobile phone you’re often browsing “passively”, as you could be waiting for a meeting to start, killing time on the elevator, or on the train or subway.
• On a mobile phone, where images are smaller or even non existent, you’re less likely to have an emotional response to advertising or promotions.
• Filling out contact forms on a phone can be difficult.
• Ask yourself, have you ever started a free trial for a SaaS on a phone, or even downloaded an ebook or white paper?

Another big problem for LinkedIn: people don’t search for products and services on LinkedIn.

People visit LinkedIn for making connections, following content from their network, and to lookup company information and/or job or sales prospect.

It’s simply not a place that you go to make purchases.

Thus, although you can laser-target groups or individuals that are in your target audience, that doesn’t mean they’re going to respond.

However, I suspect this could change with the recent Microsoft acquisition of LinkedIn.

I’m guessing Microsoft will find a way to make LinkedIn more of a search and purchase destination with Bing ads.

As I’ve pointed out recently, Google needs a B2B search platform, and maybe Microsoft and LinkedIn will be part of the solution.