Witness the ad industry’s reaction to claims it is dragging its feet on “Do Not Track,” a system to let consumers tell companies not to harvest their online personal information.

“We keep getting demagogued by the FTC,” Stu Ingis, the head of the Digital Advertising Alliance, told AdWeek. The remark came in response to a speech this week in which the head of the Federal Trade Commission suggested new rules might be on the way.

Does Ingis have reason to worry? Perhaps. Consider that after a year of relative silence, the dreaded (in the ad industry, anyway) “Do Not Track” phrase is back in the news on a regular basis. Next week, for instance, U.S. Senator Jay Rockefeller (D-W.Va)  is holding a public hearing to trumpet his do-not-track legislation. Meanwhile, Microsoft and Mozilla are setting their Internet Explorer and Firefox browsers to block third-party cookies — small, ubiquitous computer programs that record the web pages you visit.

For advertisers, these developments threaten to throw a wrench into an ad system that puts a high value on “retargeted” ads. Indeed, there is already evidence that fewer cookies means lower ad prices.

On the other hand, any type of sweeping law is unlikely. While politicians like beating the privacy drum, the details — and even the definition — of “Do Not Track” are hopelessly complicated. Companies like Google and Facebook (which are giant advertising firms) claim the term is confusing to consumers and, in some cases, have chosen to ignore browser instructions about cookies.

At the same time, these companies are doubling down on ad products that target individual users. Facebook, for instance, now lets customers buy ads based on third party data and is even partnering with retail outlets like drug stores to collect users’ offline shopping information. The social network and other tech companies, which have growing clout in Washington, will lobby hard to prevent any serious change to the current ad system.

Finally, the focus on cookies could ultimately prove to be a red herring in the”Do Not Track” debate. This is because more consumers are using mobile devices to access the internet — and these devices don’t rely on cookies for advertising in the first place.  In response, Apple has developed a sophisticated way for advertisers to target users’ devices while companies like TapAd and Adelphic have found ways to identify users no matter what device they use. In other words, any new “Do Not Track” law that targeted cookies would have a limited effect in a world where marketers follow us on our mobile devices.

The bottom line is there has been more sound and fury than usual about “Do Not Track” but that comprehensive privacy reforms are nowhere in sight.

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This situation has led a start-up named Adelphic to offers tools that let marketers identify people, not just devices. Founded by two veterans of a mobile ad network used by Apple, Adelphic claims to use 30 different “signals” to recognize patterns and information about a given smartphone user.

On Tuesday, the company got a big boost with the announcement of a new $10 million investment led by Google Ventures, the venture capital arm of the search giant. The funding appears to reflect the widespread desire for an solution to the mobile ad conundrum.

“It’s hard for brands to find people,” said co-founder Jennifer Lum, explaining the issue in a phone interview. “It’s hard to describe and package up the mobile industry to sell to audiences.”

Adelphic’s “30 signal” solution sounds intriguing, but does it work? On regular websites, advertisers can easily gather signals through cookies that record information about a user.  This task is much harder on smartphones, which collect far fewer cookies.

Lum offered few details but did say that Adelphic uses “inference algorithms” to blend a variety of data that let advertisers know if a smartphone customer had responded to previous offers. The “30 signals” are mostly a mystery, but a good guess is that they represent some combination of browsing history, log-ins, location data and more.

In any case, the $10 million could indicate that Adelphic is on to something. Lum says the company has provided analytics for 20 billion mobile ads since October.

For the mobile ad industry, the success of Adelphic’s tools could introduce more liquidity to the market as a result of advertisers gaining more confidence in the ability to reach given customer segments. The technology also lets marketers have a better chance to optimize their campaigns on the fly — using the analytics to tell if an ad campaign is working and change it if it is not.

Tuesday’s announcement will also lead to Rich Miner of Google Ventures joining Adelphic’s board. Original investors Matrix Partners, who helped put in $2 million in March, also participated in the $10 million investment.

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