This bulletin explains how sampling works in Metrc (Minnesota), including how to calculate required sample sizes by batch type, create test sample packages in Metrc, split out retention and stability samples, and transfer laboratory analysis samples to a testing facility in a compliant way.
What this Metrc Support Bulletin covers (Minnesota)
Minnesota’s Office of Cannabis Management (OCM) issued this Metrc Support Bulletin to expand on the Cannabis Technical Authority (CTA) sampling requirements. The guidance focuses on two operator pain points: determining how much material to sample from different batch sizes and entering those samples correctly in Metrc so inventory, testing status, and recordkeeping align with state expectations.
Key sampling definitions used in the bulletin
Batch (cultivation): A specific quantity of cannabis plants cultivated from the same seed or plant stock, cultivated together, intended to be harvested together, and receiving identical propagation and cultivation treatment.
Batch (flower): A specific quantity of cannabis flower harvested together that is uniform, intended to meet specifications for identity/strength/purity/composition, and receives identical sorting, drying, curing, and storage treatment.
Batch (manufactured products): A specific quantity of a specific cannabis product (including lower-potency hemp edibles and hemp-derived product types described by Minnesota law) manufactured at the same time using the same methods, equipment, and ingredients; uniform; and manufactured/packaged/labeled under a single batch production record (referenced in the bulletin as Minnesota Statutes, section 342.01, subd 7).
Compliance representative sample: A small portion of a larger batch or product intended to represent the whole batch for compliance testing.
Increments: Discrete portions of sample pulled from various locations in a batch to build the compliance representative sample.
Laboratory analysis sample: The main portion of the representative sample sent by the licensee to a testing facility for compliance analysis (referenced in the bulletin as CTA page 2).
Retention sample: A portion of the representative sample held by the licensee until six months after the product expiration date (referenced in the bulletin as CTA page 3).
Stability sample: A portion of the representative sample from the first batch of a cultivation or manufacturing process that is held by the license holder or testing facility for evaluation of shelf life.
Metrc setup: create sublocations for retention and stability
OCM recommends setting up dedicated Metrc sublocations such as Retention Samples and Stability Samples before you begin sampling. Operationally, this helps teams segregate material that should not be sold, prevents accidental transfers, and makes it easier to demonstrate control of samples during inspections.
If you need help creating sublocations, use Metrc’s in-app guidance (Metrc Expert) or contact Metrc Support.
How to calculate sample sizes (and why it matters)
The bulletin ties required sampling amounts to total batch size and product type. You calculate a compliance representative sample first, then split it into a laboratory analysis sample and a retention sample (and stability samples if required).
Important rule from the bulletin: The laboratory analysis sample size is always the compliance representative sample minus the retention sample.
Concentrates and vapes: representative, lab, and retention sizes
Batch mass ≤10 lbs (≤4.5 kg): 10 increments totaling 32 g representative sample; 22 g laboratory analysis sample; 10 g retention sample.
Batch mass 10–14 lbs (4.5–6.4 kg): 12 increments totaling 32 g representative sample; 22 g laboratory analysis sample; 10 g retention sample.
Batch mass >14 lbs (>6.4 kg): 12 increments totaling 0.5% of batch mass representative sample; laboratory analysis sample equals 0.5% of batch mass minus 10 g retention; 10 g retention sample.
Flower, infused edibles, and infused non-edibles (excluding beverages)
Batch mass ≤10 lbs (≤4.5 kg): 10 increments totaling 60 g representative sample; 40 g laboratory analysis sample; 20 g retention sample.
Batch mass 10–26.5 lbs (4.5–12 kg): 12 increments totaling 60 g representative sample; 40 g laboratory analysis sample; 20 g retention sample.
Batch mass >26.5 lbs (>12 kg): 12 increments totaling 0.5% of batch mass representative sample; laboratory analysis sample equals 0.5% of batch mass minus 20 g retention; 20 g retention sample.
Beverage batches measured by volume (gallons)
Batch volume ≤100 gal: 4 increments totaling 8 units representative sample; 4 units laboratory analysis sample; 4 units retention sample.
Batch volume 100–940 gal: 4 increments totaling 12 units representative sample; 8 units laboratory analysis sample; 4 units retention sample.
Batch volume 940–1550 gal: 6 increments totaling 14 units representative sample; 10 units laboratory analysis sample; 4 units retention sample.
Batch volume 1550–3100 gal: 8 increments totaling 16 units representative sample; 12 units laboratory analysis sample; 4 units retention sample.
Batch volume >3100 gal: 12 increments totaling 28 units representative sample; 24 units laboratory analysis sample; 4 units retention sample.
Shooters (beverage shooters under 3 oz)
Batch volume ≤1,000 units: 6 increments totaling 16 units representative sample; 10 units laboratory analysis sample; 6 units retention sample.
Batch volume 1,000–5,000 units: 8 increments totaling 18 units representative sample; 12 units laboratory analysis sample; 6 units retention sample.
Batch volume >5,000 units: 12 increments totaling 30 units representative sample; 24 units laboratory analysis sample; 6 units retention sample.
Homogeneity and stability testing: plan sample volume early
If a batch will be evaluated for homogeneity and/or stability, the bulletin emphasizes that the license holder must ensure the compliance representative sample includes enough material for those additional analyses. Practically, this means coordinating sample planning with the testing facility before you pull and package increments.
At each stability timepoint, potency and microbial content will be evaluated; for vape devices, heavy metals will also be evaluated.
Microbial minimums per stability timepoint (bulletin note): At least 10 g flower, 5 g concentrate, 10 g infused non-edible, or 25 g infused edible for each timepoint.
Worked example from the bulletin: 45 kg flower batch
The bulletin’s example begins with a bulk flower batch of 45 kg (45,000 g) intended to be tested in its final form.
Source package size: 45,000 g.
Compliance representative sample (0.5%): 225 g.
Retention sample: 20 g.
Laboratory analysis sample: 205 g (225 g minus 20 g).
How to collect a compliance representative sample (operational expectations)
OCM directs licensees to follow the CTA sampling instructions, including assembling the entire batch in a clean location under video surveillance and ensuring the required number of increments represent the full batch package. The practical compliance goal is defensible representativeness: your sampling method should be able to withstand audit scrutiny and explain why the sample reflects the entire lot.
Select a container that will not introduce contaminants or damage product during transport, and confirm any container requirements with the testing facility before sampling day to avoid rejected samples and retesting delays.
Metrc workflow: create the test sample package
After physically pulling the compliance representative sample, create a new test sample package in Metrc from the source batch package using Submit for Testing. In Metrc, the quantity on this test sample package should equal the compliance representative sample size you calculated (for example, 225 g in the worked example).
Key Metrc data entry concepts from the bulletin: Use a new package tag, choose the correct location, enter the correct quantity and unit of measure, and select Same Item so the sample remains tied to the source item. Select the appropriate lab test batch for the product being sampled. If stability testing is requested, select Stability Study T0 but do not select additional stability tests at this creation step.
Metrc workflow: split out retention and stability samples
Before transferring material to the testing facility, the bulletin instructs the licensee to remove the retention and any stability samples from the laboratory compliance sample package.
Create the retention sample package in Metrc by selecting the lab sample package and using New Packages. Enter the new package tag, location, quantity, unit of measure, and package date, and keep Same Item selected. The retention quantity should match your calculated retention size (for example, 20 g). Place it in your dedicated Retention Samples sublocation to reduce the risk of accidental sale or transfer.
Create stability sample packages the same way (also from the lab sample package), using New Packages for each required stability timepoint. Add a clear note that the package is for stability testing, and place it in a Stability Samples sublocation. The testing facility should confirm the number of timepoints and the amount required per timepoint.
Transfer the laboratory analysis sample to the testing facility
After retention and stability portions are separated, manifest (transfer) the laboratory analysis sample package to the testing facility for compliance testing. If the business and testing facility agree the lab will hold stability samples, include those stability packages on the manifest as well.
The bulletin also notes that an OCM-licensed transporter should be used to move sample(s) to the testing facility for analysis.
Practical implications for day-to-day cannabis operations
Inventory accuracy and audit readiness: The most common operational risk is misaligning physical sampling with Metrc package quantities. If the compliance representative sample is pulled but the Metrc test package is created for a different quantity, your on-hand inventory and chain of custody can become difficult to defend.
Preventing delays at the lab: Under-sizing the representative sample (especially when stability or homogeneity is required) can force re-sampling, re-manifesting, and additional hold time on saleable inventory.
Retention discipline: The retention sample is not optional recordkeeping; it is material you must control for the product’s lifetime plus six months after expiration. A dedicated Metrc sublocation makes retention custody easy to demonstrate.
Cross-team communication: Sampling touches cultivation/manufacturing, compliance, packaging, and logistics. This bulletin effectively requires teams to agree on batch boundaries, sample plans, lab requirements, and transport timing before Metrc actions are taken.
Labeling and Retail ID compliance: Distru tools to consider
DistruLabels (free): DistruLabels is a 100% free tool for creating compliant packaging and retail labels, and it can help operations align label details with Metrc requirements such as Metrc Retail ID workflows where applicable. Using a consistent labeling system reduces the risk of mismatches between what is in Metrc (item/package identity) and what appears on the unit sold.
DistruERP for larger operators: DistruERP is Distru’s comprehensive Cannabis ERP platform for larger operations that need complete supply chain management across production, inventory, compliance workflows, sales, and fulfillment. For multi-department teams, an ERP can reduce sampling-related errors by standardizing batch records, packaging runs, and traceability documentation alongside Metrc activity.
Metrc support resources referenced in the bulletin
Metrc Support: Access the support portal at https://support.metrc.com for troubleshooting and state-specific assistance.
Metrc Learn: Training resources are available at https://learn.metrc.com to build proficiency with workflows like Submit for Testing, New Packages, and transfers.
Metrc Expert: Use the in-app Metrc Expert knowledge base for step-by-step guidance directly inside the Metrc system.
