Is the Marucci Cat 9 Legal in High School Baseball? The Answer May Surprise You

Introducing the Marucci Cat 9 Baseball Bat

The Marucci Cat 9 is one of the most popular baseball bats on the market today. Marucci is known for making high-quality composite bats designed for optimal performance and feel. The Cat 9 first launched in 2017 and quickly gained a reputation as a top-tier bat in youth, high school, college and even professional leagues.

The Cat 9 uses Marucci’s AZ105 alloy, which is antimicrobial and features responsive micro-structure for better feel and forgiveness on off-center hits. It has a balanced swing weight, with a -3 length to weight ratio in the BBCOR version. The one-piece composite design reduces unwanted vibration and provides a smooth, comfortable swing. The Cat 9 produces some of the fastest swing speeds among one-piece bats.

In multiple independent bat rating and review tests, the Cat 9 consistently rates highly for its light swing weight, large sweet spot and excellent power transfer on contact. It’s one of the most popular bats among travel ball and youth league players seeking a composite bat approved for most high school and college play.

Cited from: Marucci Cat 9 Bbcor – Amazon

Rules and Regulations on Baseball Bat Design

Different leagues and associations have specific rules regarding bat design and specifications to ensure fairness and safety. High school baseball generally follows National Federation of State High School Associations (NFHS) rules. According to their 2022 Baseball Rules Book, bats must be made of wood, aluminum, magnesium, or composite material and adhere to a -3 length to weight ratio limit.

The NCAA governs bat regulations for college baseball. NCAA rules state that only aluminum/alloy or composite bats can be used, and the bat must have a -3 length to weight ratio and barrel diameter no larger than 2 5/8 inches. Composite bats must meet the Ball Exit Speed Ratio testing protocol.

Major League Baseball enforces strict regulations only allowing solid wood bats with a maximum diameter of 2.61 inches and length of 42 inches. This specification has been consistent since the late 1800s. Prior to the 1920s, bat regulations were more lenient.

Over time, governing bodies have moved to tighten bat regulations and prohibit performance enhancing designs as technology has advanced. Safety has also been a driver of rule changes, particularly the ban of aluminum and composite baseball bats in youth leagues to prevent increased ball speeds and injury risks.

Marucci Cat 9 Bat Specifications

The Marucci Cat 9 baseball bat comes in both alloy and composite models, with some key specifications defining the design and performance of each bat:

The alloy Marucci Cat 9 has a standard 2 5/8 inch barrel diameter, common to most high school, college and professional bats. The bat features Marucci’s patented AV2 alloy, which is carefully calibrated for optimal strength and response through the barrel.

The composite Marucci Cat 9 has a slightly larger 2 3/4 inch barrel diameter. The bat is constructed using Marucci’s carbon composite material, which allows for a lighter swing weight and bigger barrel profile while maintaining durability.

For length to weight ratio, the Marucci Cat 9 comes in a range of drop weights from -8 to -5, meaning an increase in bat length of 8 to 5 ounces relative to bat weight respectively. This provides players options for maximizing bat speed or control.

The alloy and composite Cat 9 models have similar constructions in terms of Marucci’s signature Anti-Vibration knob and longitudinal grooved barrel technology. Both aim to minimize unwanted vibration and optimize performance through the sweet spot.

According to Marucci’s website,
key specifications for the Cat 9 composite are:

  • 2 5/8″ barrel diameter
  • -3 length to weight ratio
  • Carbon composite construction
  • Compliance with High School Regulations

    The Marucci Cat 9 baseball bat complies with the regulations for high school baseball set by the National Federation of State High School Associations (NFHS). According to the NFHS, the maximum barrel diameter for non-wood bats is 2 5/8 inches, and the bat must have a BBCOR certification.

    The Marucci Cat 9 has a barrel diameter of 2 5/8 inches, meeting the NFHS specification. It is also BBCOR certified, with a BBCOR stamp on the bat to indicate compliance. BBCOR stands for “Batted Ball Coefficient of Restitution” and regulates the trampoline effect of non-wood bats to be comparable to wood bats (

    In addition, the Cat 9 meets other high school regulations related to the bat’s length-to-weight ratio, construction materials, and absence of sensors or devices. The only potential issue is that some individual states or leagues ban certain composite bat models, like the Marucci Cat 9, due to performance concerns. But generally, the Cat 9 adheres to the NFHS’s national guidelines.

    Compliance with College Regulations

    The Marucci Cat 9 is compliant for use in NCAA college baseball. According to the NCAA’s list of prohibited BBCORE bats updated February 2020, the Marucci Cat 9 is not banned and meets the BBCOR bat performance standard required for use in NCAA competition (source).

    All Marucci composite bats like the Cat 9 are certified BBCOR .50 bats, indicating adherence to the Bat-Ball Coefficient of Restitution standards imposed by the NCAA (source). The BBCOR certification regulates the trampoline effect and limits how much energy can be transferred to the ball off the bat barrel.

    To confirm a specific Cat 9 bat meets NCAA requirements, players can look up their bat’s unique serial number on Marucci’s website and verify BBCOR certification (source). As long as the Cat 9 displays the BBCOR .50 logo and is not specifically prohibited, it is legal for NCAA college baseball play.

    Compliance with MLB Regulations

    The MLB has strict regulations on bat specifications for professional play. According to the official MLB rules, bats must be made of a solid piece of wood or have a wood barrel and meet the following requirements:

    • Bat shall not be more than 2.61 inches in diameter at thickest part
    • Bat shall not be more than 42 inches in length
    • Bat shall not weigh, numerically, more than three ounces less than length of bat (e.g., a 33-inch-long bat cannot weigh less than 30 ounces)

    The Marucci Cat 9 is a one-piece metal bat, so it does not comply with the wood or wood barrel specifications. Metal and composite bats like the Cat 9 are not permitted in official MLB games. While the Cat 9 is an excellent performance bat for youth, high school, and college play, it cannot be used by professional players in the MLB.

    According to Marucci’s website, the Cat 9 is intended for elite travel ball and college players, not professionals. It has never been approved for use in the MLB. Players in the majors must swing wood or wood composite bats that meet the league’s guidelines.

    Quality and Safety Certifications

    The Marucci Cat 9 has passed extensive safety testing and meets quality standards for multiple leagues and organizations. According to Marucci Sports, all of their metal bats like the Cat 9 are certified by USSSA, USA Baseball, the National Federation of State High School Associations (NFHS), and the National Collegiate Athletic Association (NCAA) (

    For USSSA certification, bats must have a Bat Performance Factor (BPF) of 1.15 or less. This ensures the bat does not hit the ball too fast or hard, reducing safety risks. Marucci designs the Cat 9 to comply with the USSSA BPF standard.

    USA Baseball created a new standard in 2018 called the USA Baseball Bat Standard (USABat). All Marucci metal bats like the Cat 9 meet the USABat protocols as well. USABat certification focuses on balancing bat performance with youth player safety.

    NFHS is the governing body for high school sports rules. Marucci indicates the Cat 9 is fully compliant with NFHS bat standards for high school baseball. This ensures high school players can safely use the Cat 9 bat.

    For collegiate play, the Cat 9 adheres to NCAA bat requirements. Marucci works closely with the NCAA to guarantee compliance and safety for college players.

    In summary, Marucci puts the Cat 9 through extensive safety testing and certification processes. This ensures the bat meets applicable standards and requirements for youth leagues, high schools, colleges, and more (–10-usssa-baseball-bat–msbc910/33424/). Players can trust they are getting a high-quality and safe bat with the Cat 9.

    Why Certain Leagues Ban the Cat 9

    Some leagues, such as USSSA, have chosen to ban the use of the Marucci Cat 9 bat due to concerns about performance and fairness. USSSA has very particular bat standards and regularly updates its list of approved and banned bats. According to one source, the Marucci Cat 9 hype fire model will likely eventually get banned by USSSA as they aim to keep a level playing field

    The main factors that can lead USSSA or other leagues to ban a particular bat model are:

    • Bat performance exceeding current standards
    • Safety issues and concerns around bat durability
    • Maintaining fairness of play and integrity of the game

    USSSA has banned the Marucci Cat 9 in certain drop sizes, such as the -5, -8, and -9 lengths. However, they still allow other drop sizes like -3. The banned Cat 9 models were determined to create potential performance advantages exceeding USSSA standards (Source).

    While allowed for use in many leagues, some have elected to ban the Marucci Cat 9 due to its strong hitting performance and perceived improvement over other composite bats. However, Marucci asserts that all their bats are certified and compliant with the rules.

    The Ongoing Debate on Composite Bats

    Composite bats have been a source of controversy and debate in many baseball leagues. Composite bats are made from a graphite, fiberglass, or carbon fiber material as opposed to traditional aluminum or wood bats. Composite bats have performance advantages due to a “trampoline effect” that allows the ball to spring off the bat faster and farther. However, many argue this gives an unfair performance advantage and raises safety concerns.

    Those in favor of composite bats point to the exciting increase in offense and argue the bats are safer by reducing the risk of broken bats. Manufacturers claim composite materials improve durability and allow for innovative designs. However, critics argue composite bats undermine the integrity of the game by artificially inflating offensive statistics. There are also concerns that non-wood bats are contrary to the spirit of the game and detract from developing essential baseball skills. Some regulators even claim certain composite bat designs can endanger pitchers due to increased ball speeds coming off the bat.

    In response to performance concerns, many leagues have moved to regulate or ban composite bats. Little League Baseball banned composite bats in 2011 following an independent study. While use varies across high school and collegiate leagues, most have implemented testing and certification programs to regulate performance of non-wood bats. The debate continues around finding the right balance between innovation and maintaining the integrity of the game.

    The Bottom Line on Marucci Cat 9 Legality

    In summary, the Marucci Cat 9 is legal for use in most high school and collegiate baseball leagues, but has been banned from use in some leagues due to performance standards. The bat meets the BBCOR regulations for high school and NCAA play with a -3 length to weight ratio and BBCOR certification stamp. However, some high school athletic associations, such as the National Federation of State High School Associations, have banned the Cat 9 due to excessive performance seen at the varsity level (1).

    At the professional level, the Cat 9 does not meet MLB regulations and is not legal for use in official MLB games. MLB regulations require wood bats only. The Cat 9 is a one-piece composite bat, making it illegal for MLB games (2).

    Looking ahead, as technology continues to improve baseball bat designs, high school and collegiate leagues may further restrict or ban composite bats like the Cat 9 to maintain a balance of offense and defensive play. Manufacturers will need to innovate within the bounds of new bat regulations. For now, most amateur players can swing the Cat 9, but be sure to check your local league rules before stepping into the batter’s box.




    Scroll to Top