Flock Bio: Custom Pooled DNA Libraries for Screens and Variant Panels
A Bay Area team that designs, builds and sequence-checks pooled DNA libraries end to end, now orderable on the Cypher AI Marketplace.
By Cypher AI ·
WHAT IS FLOCK BIO?
Flock Bio is a San Francisco Bay Area company that builds custom pooled DNA libraries, with NGS quality control on every build. The team has built libraries together for more than six years, for CRISPR screens, enzyme evolution, lineage tracing and massively parallel reporter assays (MPRAs). As of October 2026, Flock Bio's Pooled DNA Libraries service is listed on the Cypher AI Marketplace, a catalog of lab services that scientists can browse and order from.
Mat Falkowski, Flock Bio's CEO, has more than 20 years of experience constructing DNA libraries. Matthew Youngblut, co-founder and chief scientific officer, brings additional expertise, having previously worked at Ginkgo Bioworks and Twist Bioscience.
WHAT PROBLEM DOES AN END-TO-END LIBRARY BUILD SOLVE?
An end-to-end build puts one team in charge of the whole library, from design review to QC. A pooled library passes through sequence design, oligo ordering, assembly, amplification, QC and normalization before it is ready to use. Each step can add bias, uneven representation or delay. Those problems grow when the steps are split across teams or vendors.
Uneven representation can decide whether a screen is readable. In a pooled CRISPR screen or an MPRA, a variant that is badly under-represented may drop out before the assay starts. A heavily over-represented variant can crowd the readout. Misassembled clones add background that carries no designed variant at all.
Flock Bio builds for low background and even representation. Flock reports fewer than 1% misassembly products, with background typically between 0.01% and 0.1%. Every library is sequenced and analyzed for quality and diversity before it ships.
WHAT CAN YOU ORDER FROM FLOCK BIO ON CYPHER AI?
As of October 2026, Flock Bio lists one service on the Cypher AI Marketplace, called Pooled DNA Libraries. It covers libraries with one, two or three variable insert regions. One of those regions can be a barcode. The service is priced by quote.
Flock Bio offers two service levels. Cloning Lite is a single-insert pool with a sequencing snapshot. Full Service covers multi-insert libraries, full NGS QC and analysis, and maxiprep DNA. Teams that aren't sure which fits can ask Flock to recommend one.
Libraries ship ready for cells, with or without endotoxin removal. Flock Bio can run up to four rounds of cloning for libraries with several variable domains.
WHAT KINDS OF LIBRARIES DOES FLOCK BIO BUILD?
Flock Bio builds libraries for genetic medicines, protein engineering, synthetic biology and crop science. Examples include barcoded promoter variants for MPRAs, 3' UTR variants for mRNA stability testing and AAV capsid variants for tissue targeting.
Combinatorial designs are part of the range. One example is a lentiviral CAR-T library that varies domains at three positions, with barcodes linked to each combination. A team can then read out which architecture performed best after a single pooled screen.
FREQUENTLY ASKED QUESTIONS
How long does a pooled DNA library from Flock Bio take? Cloning Lite libraries ship in as few as 6 business days. The Marketplace listing estimates 1 to 5 weeks for a build.
What QC comes with a Flock Bio library? Every Flock Bio build includes NGS and bioinformatics analysis, and each library ships with a QC report. Flock runs short- and long-read sequencing on Element AVITI, Illumina NovaSeq and PacBio Revio.
Can I send my own DNA or vector to Flock Bio? Yes. You can send your own insert DNA and vector, send the vector and have Flock order the DNA, or have Flock handle both. DNA that Flock orders is billed at cost, and Flock charges for cloning and QC. Flock works with standard backbones such as pUC, pMB1 and ColE1, and with AAV, lentiviral and low-copy vectors.
HOW DO YOU ORDER FROM FLOCK BIO ON CYPHER AI?
You can browse Flock Bio's listing at cypherbio.ai/services without an account. To request a quote, create a free Cypher AI account. The request form asks what the library is for, roughly how many unique variants it needs and whether it needs barcodes. You can also attach sequence files or a vector map.
Flock Bio reviews the design before the build starts and sends you the quote. You pay Flock Bio directly.