Series 99 common mistakes
Series 99 · Understand the traps and how to avoid them.
Answers every settlement question on a T+2 assumption and carries that assumption into fail, close-out, and extension calculations.
Most candidates built their mental model of settlement before the industry moved to a one-day standard, and general finance background material still references the older cycle. Once the wrong cycle is fixed in working memory, every downstream date is wrong even when the reasoning is sound.
What to do instead
Before touching any date, write the cycle for the specific instrument on scratch paper and note that the standard cycle for most U.S. securities is now T+1. Then recompute the fail date, the close-out window, and any extension from that written cycle rather than from memory.
Computes the customer protection reserve by tallying only the debit side (customer securities owed) and omits the credit side items such as free credit balances and amounts due for partially paid securities.
The reserve formula is taught as a subtraction, so candidates look for one number to subtract from another and skip classification of the big-ticket credit items. Free credit balances feel like firm money because the firm is holding cash.
What to do instead
Practise the formula in both directions on paper and memorise the classification of the five or six recurring items (free credit balances, money payable for partially paid securities, securities borrowed or loaned, fails to receive and deliver). Classify first, compute second.
Treats an asset as allowable net capital because it looks safe or because it is a receivable from a customer.
Candidates substitute intuition about credit quality for the rule's bright-line list and haircut table. The exam deliberately offers plausible-sounding assets that are specifically excluded.
What to do instead
Work from a written allowable-assets checklist and a short haircut table. Adopt the rule: if the item is not affirmatively on the allowable list, it is non-allowable, regardless of how creditworthy it appears.
Cites Regulation T percentages when the question is actually about a maintenance call that arises after the trade, and vice versa.
Both rules produce familiar 50% and 25%-style numbers and study outlines place them side by side, so the numbers blur together even when the candidate understands margin in principle.
What to do instead
Anchor each number to an actor and a moment: Regulation T governs the extension of initial credit and payment periods at the time of purchase; FINRA margin rules govern maintenance after settlement. For each practice item, first label the moment (at purchase vs. post-settlement), then pick the rule.
Selects the correct required action on a supervisory or regulatory item but attaches the wrong deadline or filing window.
Items are engineered around time triggers, and candidates memorise the action while treating the clock as a detail. Many deadlines are also paired in the rules (notification to the regulator versus notice to the customer), which invites substitution.
What to do instead
Build a single one-page table of time triggers covering the notification, filing, and retention deadlines the outline lists, and self-quiz on the clock only, hiding the action column. Rebuild the table from blank paper weekly.
Applies one default recordkeeping retention period to every record and ignores the differing accessibility window.
Several different retention numbers appear across the books-and-records rules, and candidates memorise a single favourite number rather than the default plus its exceptions. The distinction between total retention and the period a record must be readily accessible is easy to overlook.
What to do instead
Memorise the default retention period together with the shorter window during which records must be readily accessible, then keep a short exceptions list of the specific records the outline names. When an item cites a non-default period, verify it against that exceptions list before selecting.
Lets the firm's internal vocabulary decide whether a customer communication is a complaint, so a written grievance in an email is logged as an inquiry and no further action is taken.
Firms use different internal labels for service issues, questions, and complaints, and candidates unconsciously map the exam's definition onto whatever their own firm calls things. The regulatory definition turns on whether the grievance is written, not on the firm's ticketing category.
What to do instead
Memorise the regulatory definition of a complaint as a written grievance, and the handling obligations that attach once that threshold is met. Then test edge cases explicitly: oral versus written, email versus chat, and a written question that also alleges harm.
Analyses an outside activity under the private securities transaction rule, or a securities transaction under the outside business activity rule, and gives the notice, approval, and compensation answer that belongs to the other rule.
Both rules involve activity and compensation away from the firm, and the two are frequently taught in the same paragraph, so the trigger conditions collapse into one blurry idea.
What to do instead
Use a two-question screen before choosing a rule: is the activity a securities transaction, and is the representative receiving compensation for it? Both yes points to the private securities transaction rule; anything that is not a securities transaction points to the outside business activity rule. State the screen in the answer.
Applies retail-communication principal pre-approval and filing requirements to institutional communications or to correspondence, or the reverse.
The three categories share a definitional base and differ only in approval, filing, and retention consequences, so candidates remember that the categories exist but not the grid that separates them.
What to do instead
Memorise a three-column grid (retail, institutional, correspondence) against three rows (principal pre-approval, filing with the regulator, retention location). Recite the grid from memory before answering any communications item, then place the fact pattern in a column.
After identifying a suspicious transaction, chooses the answer that documents the concern in the customer's file or that requests additional information from the customer, rather than the answer that preserves confidentiality and reports internally.
Documentation is the instinctive response drilled in most operational training, and the prohibition on disclosing a suspicious activity report is taught as a footnote rather than as its own testable rule. Candidates also mistake customer outreach for due diligence when it would tip off the subject.
What to do instead
Treat the confidentiality prohibition as a standalone rule: no disclosure to the subject, no notation in the customer record, and sharing limited to those with a need to know. When an answer option involves telling the customer or annotating the file, eliminate it before evaluating the remaining options.