Dennis D. McDonald ( consults from Alexandria Virginia. His services include writing & research, proposal development, and project management.

What is "Personal Data?"

By Dennis D. McDonald

When you start researching personal data and the definition of ownership, you quickly get caught up in questions about "what is property?" and "what data about me do I really own?"

These are tricky questions.

First, we're talking about data, not physical property. Even if we were dealing with physical property here, there could still be disagreement about the nature of ownership of the property, as pointed out by Waldron in his discussion of private, common, and communal property (Waldron, chapter 2). Even in the case of private property, Waldron points out, there are justifiably many situations where one's ownership must be balanced against other needs and requirements. This sounds similar to my belief that my desire for privacy can be balanced with commercial and governmental needs for access to my “personal data.”

Data, unlike physical property, is easily cloned and copied without depleting the original. The same can't be said for physical property, which can be difficult to copy and distribute. In fact, the basic scarcity of physical goods is one of the things that contribute to their perceived value, and price. This is one of the reasons that DRM [digital rights management] schemes are viewed as so important by some intellectual property owners. The idea is that such schemes will prevent unauthorized or uncompensated duplication and distribution. (One of the more interesting blogs I’ve run across lately is Robert Weber’s “Managing Rights Management” which is here.)

My concern is more with "personal" data such my social security number, my medical history, data about my credit card transactions, details of my family life, my travel behavior -- all of which may be recorded and stored in systems both remote from me and outside my awareness and control.

Viewed in the abstract these numbers and text have no value. Taken together in connection with information about other things about me (where I live, what I buy, what I watch and listen to, etc.) they can take on value. This value is based not on the data themselves but on what they (theoretically) represent about the type of person I am and might be willing to do in the future. If I have purchased electronics from in the past, for example, I am more likely than someone who has not done so to purchase electronics again from Amazon and its competitors might be interested in knowing that kind of information about me and others like me.

This information about my identity includes my capacity to buy certain things. My data become valuable because they are associated with certain potential actions I might take -- such as buying the products an advertiser wants a person like me to buy. Furthermore, the better data about me are in predicting my potential behavior, the more important it will be for a potential vendor to have that data. Why should a vendor settle for just knowing me by my zip code, for example, when information about my actual income, the type of car I drive, my eye color, and whether or not I subscribe to digital cable can also be obtained? So, data about me and my behavior, which I am collectively referring to here as "personal data," has economic value to someone.

That is not to say that my personal data may not have other types of value. My medical history, for example, may indicate whether or not I am prone to a particular malady or disease. While insurance companies may want to know this when sizing me up for a policy, the Federal Government may also be interested for matters of public health in order to plan health related policies and programs.

Another thing is that I don't actually create all the data that are associated with me. That makes personal data different from intellectual property that is the result of a creative act of some sort. My social security number did not spring from my fertile imagination; it was assigned by a government bureaucracy. My parents gave me my name. And I did not actually collect and organize any historical data about my financial transactions --- my banks, credit card companies, and others are happy to do that as part of the mechanisms they have evolved to manage their business relationships with me and the companies I frequent.

When I look at this constellation of data that surrounds and describes me, I am simultaneously amazed by the sheer volume and complexity. I am also sobered by the fact that I have very little direct control over how this information is used, or how accurate it actually is.

Fundamentally, though, I believe in paying a fair price in return for a desired good or service. And I believe that others should also pay a fair price for value that I provide. I know, for example, that if I buy food at my local supermarket, I get a "discount" if I use my store card. This enables the store to amass vast quantities of information about my and my family's buying habits, including our toothpaste preferences and whether or not we prefer microwave over bag popcorn. I receive from the supermarket company a discount for using my card, so I expect that the store will take advantage of what they know about me to tailor advertising campaigns as well as those cash register coupons that are custom printed whenever I cash out. I also know that if I serve on a panel for a market research company or agree to provide market research information in return for a cash payment, I am also being compensated information about my personal views in relation to information about my demographics and financial and purchasing behavior.

In summary, as I go through life, a great cloud of information is amassed about me. Some of it I create on my own or is generated as a direct result of actions I take. Some of this information is totally public and generally available -- my name and address, for example.

Some of this information is not sensitive. Some I would prefer to keep private, some I might reveal if I feel it is justified. Do I “own” all this information, even the information that is gathered by third parties about me without my knowledge?

Based on the little research I’ve done so far, I don’t think that the word “own” is entirely appropriate here, but there are certain similarities that I intend to explore further. For example, this “constellation” of information that surrounds and follows me will decrease in value precipitously when I eventually drop dead.

Why, for example, would Comcast after I’m dead want to send me ANOTHER one of those special offer postcards for high speed Internet access when I tell their telemarketers 2 or 3 times every month that I’m not interested?

But seriously, the fact that the value of this information would change radically in the event of my death or incapacitation does suggest that there is a certain cause-and-effect relationship between my behavior and the value of the information associated with me even if, strictly speaking, I don’t “own” this information. I'll discuss this point more in the future.


  1. Waldron, Jeremy, The Right to Private Property. New York: Oxford University Press, 1988.

Copyright (c) 2005 by Dennis D. McDonald

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