Richard Jay Lipton (born September 6, 1946) is an American computer scientist who is Associate Dean of Research, Professor, and the Frederick G. Storey Chair in Computing in the College of Computing at the Georgia Institute of Technology. He has worked in computer science theory, cryptography, and DNA computing.

In 1968, Lipton received his undergraduate degree in mathematics from Case Western Reserve University. In 1973, he received his Ph.D. from Carnegie Mellon University; his dissertation, supervised by David Parnas, is entitled On Synchronization Primitive Systems. After graduating, Lipton taught at Yale 1973–1978, at Berkeley 1978–1980, and then at Princeton 1980–2000. Since 2000, Lipton has been at Georgia Tech. While at Princeton, Lipton worked in the field of DNA computing. Since 1996, Lipton has been the chief consulting scientist at Telcordia. In 1999, Lipton was elected a member of the National Academy of Engineering for the application of computer science theory to practice.

In 1980, along with Richard M. Karp, Lipton proved that if SAT can be solved by Boolean circuits with a polynomial number of logic gates, then the polynomial hierarchy collapses to its second level.

Showing that a program P has some property is a simple process if the actions inside the program are uninterruptible. However, when the action is interruptible, Lipton showed that through a type of reduction and analysis, it can be shown that the reduced program has that property if and only if the original program has the property. If the reduction is done by treating interruptible operations as one large uninterruptible action, even with these relaxed conditions properties can be proven for a program P. Thus, correctness proofs of a parallel system can often be greatly simplified.

Lipton studied and created database security models on how and when to restrict the queries made by users of a database such that private or secret information will not be leaked. For example, querying a database of campaign donations could allow the user to discover the individual donations to political candidates or organizations. If given access to averages of data and unrestricted query access, a user could exploit the properties of those averages to gain illicit information. These queries are considered to have large "overlap" creating the insecurity. By bounding the "overlap" and number of queries, a secure database can be achieved.

Richard Lipton with Andrew Tomkins introduced a randomized online interval scheduling algorithm, the 2-size version being strongly competitive, and the k-size version achieving O(log${\displaystyle \vartriangle ^{1+\epsilon }}$), as well as demonstrating a theoretical lower-bound of O(log${\displaystyle \vartriangle }$). This algorithm uses a private-coin for randomization and a "virtual" choice to fool a medium adversary.

Being presented with an event the user must decide whether or not to include the event in the schedule. The 2-size virtual algorithm is described by how it reacts to 1-interval or k-intervals being presented by the adversary:

Again, this 2-size algorithm is shown to be strongly-competitive. The generalized k-size algorithm which is similar to the 2-size algorithm is then shown to be O(log${\displaystyle \vartriangle ^{1+\epsilon }}$)-competitive.