BREAKING  Rarebird calls paraxanthine “the third coffee” 2 US patents on Px coffee $1M NSF grant to grow paraxanthine with enzymes Named Best New Product by the Specialty Coffee Association 75% of drinkers reach for it in the afternoon 60mg Px, zero caffeine crash Backed by Y Combinator & First Round Capital BREAKING  Rarebird calls paraxanthine “the third coffee” 2 US patents on Px coffee $1M NSF grant to grow paraxanthine with enzymes Named Best New Product by the Specialty Coffee Association 75% of drinkers reach for it in the afternoon 60mg Px, zero caffeine crash Backed by Y Combinator & First Round Capital
Company Dossier • Food & Beverage • New York

Rarebird took the caffeine out - and put something smarter back in.

A specialty coffee company that runs on paraxanthine, the molecule your body makes from caffeine anyway.

2020
Founded
60mg
Px / serving
$9M+
Raised
4.9★
345+ reviews
Rarebird Coffee logo
EXHIBIT A: The wordmark of a coffee that behaves.
The Scene

3 p.m., and nobody's afraid of the cup.

It is mid-afternoon in an office somewhere, and a coffee is being poured - which is the strange part. Most people have long since sworn off the second cup by now; they know the deal. A 3 p.m. coffee is a bargain with midnight, and midnight always collects. But this cup is a Rarebird, and the person drinking it is not bargaining with anything. No jitter. No tightening in the chest. No lying awake later replaying the day. Just focus, and then, hours from now, sleep. This is the quiet trick Rarebird has built a company around: coffee that behaves.

Here is the sleight of hand. Rarebird's Px Coffee contains no caffeine at all. Instead it carries paraxanthine - the compound your own liver produces when it breaks caffeine down. Roughly 70% of the caffeine you drink eventually becomes paraxanthine; it just takes most of the day to get there. Rarebird decided to skip the wait and deliver the finished product.

If you're going to have Px coffee, you need to work with Rarebird.
- Dr. Jeffrey Dietrich, Founder & CEO
The Molecule

Caffeine's calmer twin.

Paraxanthine (Px) does the useful things caffeine does - alertness, focus, a clean lift - but early research points to fewer of the ugly ones. It has a shorter half-life, so it clears before bedtime, and it sidesteps the sharp adrenaline and cortisol spikes that turn a morning cup into a mild fight-or-flight response.

Caffeine anxiety, it turns out, isn't a personal failing. For a meaningful slice of coffee drinkers, it's genetic - specific variants (SNPs) that make the nervous system read caffeine as a threat. Those are exactly the people the coffee industry has quietly ignored, offering them decaf and a shrug.

Rarebird built for them. The company runs on a single conviction: a product you use every single day should make your mind and body work better, not tax them. That's the whole thesis behind the name of one of its blends and behind the brand itself - coffee as an intentional wellness ritual, not a chemical debt.

The science has receipts. Rarebird completed a self-GRAS (Generally Recognized as Safe) determination for paraxanthine in 2022, holds two US patents on Px coffee and its production, and has won two National Science Foundation research grants - including $1M in 2025 - to develop a biological, enzyme-catalyzed way to make Px at scale.

None of this would matter if it tasted like a compromise. It doesn't: the Specialty Coffee Association named Rarebird Px a “Best New Product,” a rare nod for anything that starts life as decaf.

By The Numbers

What the early data says.

92%
felt better on Px vs. caffeine
75%
drink it in the afternoon
67%
reported better sleep
70%
of caffeine becomes Px in your body
The Method

How you put a molecule back into a bean.

Rarebird calls it reverse-infusion. The process starts where decaf ends - and then runs backward.

1

Start with clean beans

Single-origin, high-altitude Colombian Arabica, decaffeinated with a sugarcane ethyl-acetate method. No methylene chloride.

2

Run it backward

Instead of pulling caffeine out, Rarebird uses an aqueous infusion to drive 60mg of paraxanthine back into the green bean.

3

Roast fresh, ship fast

Beans are roasted in small batches, tested for mold and mycotoxins by third-party labs, and shipped shortly after roasting.

Head To Head

Px vs. caffeine, roughly speaking.

An illustrative comparison of the traits Rarebird's customers care about. Directional, not clinical.

Clean alertness & focus
Jitters & anxiety (lower is better)
Sleep disruption (lower is better)
ParaxanthineCaffeine
The Builder

A bioengineer's second act.

JD

Dr. Jeffrey Dietrich

FOUNDER & CEO

Dietrich earned his PhD in bioengineering at UC Berkeley in Jay Keasling's lab, building biomanufacturing technology. He then spent nearly nine years as CTO of Lygos, a biotech turning bacteria into bio-based industrial chemicals. Frustrated by his own caffeine sensitivity - and unable to find anything better - he pointed the same toolkit at his morning cup. Co-founder Ann Dunn Andracchio serves as Chief Business Officer.

What You Can Buy

Three ways to drink it.

Whole Bean / Ground

Single-origin Colombian decaf, freshly roasted and reverse-infused with 60mg of Px per serving. Sold by the bag, direct or via Amazon.

Px Coffee Pods

Single-serve pods for single-cup brewers. Same jitter-free, sleep-friendly energy, zero grinding required.

Subscription

Fresh-roasted Px delivered monthly (launched at $18/bag), shipped shortly after roasting so it never sits.

What if coffee could feel better?
- The question that started Rarebird
The Record

How it got here.

2020
Rarebird founded; joins Y Combinator's Summer 2020 batch.
2022
Completes a self-GRAS determination for paraxanthine.
FEB 2023
First bags of Px Coffee begin shipping.
AUG 2023
Launches $18/bag subscription; seed round co-led by AgFunder closes.
JAN 2024
First US patent (11,872,232) issued for its caffeine alternative.
2025
Second US patent issued; wins $1M NSF grant; reports $1M in fresh financing.
Amusements

Five things worth knowing.

Go Deeper

Watch, read, follow.

The Scene, Revisited

Back at 3 p.m.

Return to that afternoon office. The cup is empty now, and here is what didn't happen: the person didn't crash at four, didn't white-knuckle a deadline through a wave of jitters, didn't lie awake at midnight settling the tab. They just worked, and then went home, and then slept. Rarebird's whole ambition fits inside that unremarkable evening. The company isn't trying to sell a novelty; it's trying to erase the fine print that coffee has always carried - and to make “Px” the third word on every cafe menu. If it works, the most radical thing about a 3 p.m. coffee will be that nobody thinks twice about it.